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  • Science
    Dinosaurs flourished and dominated the earth for about 186 million years, during the Mesozoic Era. Dinosaurs went extinct at the end of the Mesozoic era and at the beginning of the Paleogene...

    Asked by sourodeep98 on via web

    1 educator answer.

  • Science
    The chemical reaction that occurs when effervescent tablets are placed in water is as follows: Reaction in Words: Citric Acid + Sodium Bicarbonate, yields Water + Carbon Dioxide + Sodium Citrate...

    Asked by michaelnien321 on via web

    1 educator answer.

  • Science
    William T. Piper, Sr. was an aviation industrialist early in the history of the industry. He served in the Army during the Spanish-American War then returned to the oil business in Pennsylvania....

    Asked by maylita on via web

    1 educator answer.

  • Science
    This is a stoichiometry question. Most stoichiometry calculations use one or more of the following mole conversion factors: 1 mole (mol) = molar mass of the substance in grams (molar mass must be...

    Asked by daclark167350 on via web

    1 educator answer.

  • Science
    One can think of a lake or a pond as a small ecosystem. In this system, there are primary producers (phytoplanktons), consumers (zooplanktons) and decomposers. The primary producers carry out...

    Asked by user7472282 on via web

    1 educator answer.

  • Science
    Hello, In general when you analyze something, you study it and all of the components which make up an object. In chemistry, you break down a substance into its constituent elements. For example,...

    Asked by user8986570 on via web

    1 educator answer.

  • Science
    When we heat a substance, its molecules absorb this heat energy and their kinetic energies increase. This results in weakening of bonds holding these particles together and we observe a change of...

    Asked by user665346 on via web

    1 educator answer.

  • Science
    The larynx is part of the respiratory system. It is located in the neck, between the trachea and pharynx. The larynx’s structure is tube-shaped. The length of the larynx is approximately 5 inches...

    Asked by lydiatutengaehe on via web

    1 educator answer.

  • Science
    Enzymes are proteins that act as catalysts to speed up the rate of a biochemical reaction. Some enzymes are specific to one reaction only, while most can act on multiple reactions with similar...

    Asked by jamekarose on via web

    1 educator answer.

  • Science
    Energy is definitely an integral part of our life, whether we talk about electrical energy for various appliances or fuels for cooking or transportation. We can hardly think about life without...

    Asked by briannahakes24 on via web

    1 educator answer.

  • Science
    Chemical reactions occur when the atomic structure of reactants are rearranged to make new products. The following are signs that a chemical reaction may have occurred: 1. The formation of a...

    Asked by millicynt25 on via web

    1 educator answer.

  • Science
    Hello! The maximum distance is reached when the angle of elevation is 45°. Denote the initial speed in question as `V_0` and consider the projection of motion on the horizontal and vertical axes....

    Asked by user2768982 on via web

    1 educator answer.

  • Science
    Prokaryotes and eukaryotes are classifications of organisms. Prokaryotes are single cell organism, such as bacteria. Eukaryotes, on the other hand, are multi cellular organisms, such as plants,...

    Asked by sakirsch731 on via web

    1 educator answer.

  • Science
    When a chemical reaction takes place, one or more substances react to form one or more different substances. The reacting species are known as the reactants and the species that are produced are...

    Asked by aneladjenkins on via web

    1 educator answer.

  • Science
    Small animals face the biggest challenges in terms of competition for resources and predation by larger predators. Animals need resources such as food, water, light, habitat, etc. and they are in...

    Asked by katyebrownye on via web

    1 educator answer.

  • Science
    The distance traveled by the ball is given as 139 m and the average speed of the ball (through the air) is 13 m/s. Speed is defined as the ratio of distance traveled to time taken. In other words,...

    Asked by louisyacino on via web

    1 educator answer.

  • Science
    There are six important functions that take place in the digestive system as food turns from nutrients into waste. The six include: Ingestion Secretion Mixing and movement Digestion Absorption...

    Asked by maysaadri on via web

    1 educator answer.

  • Science
    Zoomastigine group includes protozoa that use flagella for locomotion purposes. Protozoans do not have chloroplasts. Protists have one or more flagella, and some groups may have pseudopodia added,...

    Asked by user3409642 on via web

    1 educator answer.

  • Science
    Weathering is the process by which natural elements, such as water, wind, plants, etc. break down rocks and soil. In this process, Earth's landform changes. Think about how a plant can have...

    Asked by monkeee2004 on via web

    1 educator answer.

  • Science
    Newtown's Second Law of Motion describes the relationship between the amount of force on an object, the objects mass and acceleration. The equation for this is `F=MA` . This means that the amount...

    Asked by itstyeguy123456789 on via web

    1 educator answer.

  • Science
    The key to writing the formula for a simple compound (i.e. one with two elements), is to determine whether the compound is ionic or covalent. We can do this by determining whether each element in...

    Asked by caitlynroy888 on via web

    1 educator answer.

  • Science
    As time elapses after exercise, a person's pulse rate should decrease until his/her resting pulse rate is reached. Energy is produced in the mitochondria of your cells during a process called...

    Asked by itaysadr on via web

    1 educator answer.

  • Science
    Our calendar year is based (somewhat loosely) on the amount of time Earth takes to complete one orbit around the Sun. This time period is known as a solar year and is about 365 days and 6 hours...

    Asked by anvikayadav15 on via web

    1 educator answer.

  • Science
    The color of one's stool is affected by his/her diet and the amount of bile produced in his/her intestinal tract. Bile is a fluid that contains enzymes that aid the digestion of lipids (fats). It...

    Asked by efurball on via web

    1 educator answer.

  • Science
    Hello! After an object was thrown, the only force acting on it is the gravity force (if we ignore air resistance). It acts downwards and is constant near Earth's surface. For an object of mass `m`...

    Asked by whoodakhid11 on via web

    1 educator answer.

  • Science
    Cod liver oil contains rich amount of two vitamins. The two vitamins that cod liver oil is rich in is vitamin A and vitamin D. Vitamin A is important for eye health. Vitamin D is important for...

    Asked by user9609496 on via web

    1 educator answer.

  • Science
    Speed is the ratio of distance traveled to time taken and is a scalar quantity (that is, has only magnitude, but no direction). In comparison, velocity is the ratio of displacement to time taken...

    Asked by amir522 on via web

    1 educator answer.

  • Science
    There are two ways to lose weight--- decrease the input of calories coming from food, or increase the output of calories coming from exercise. If the amount of calorie input (food) is less than the...

    Asked by jheng3 on via web

    1 educator answer.

  • Science
    The theoretical yield of copper is the maximum amount that can be produced starting with a given quantity of a reactant, in this case 2.07 grams of aluminum. The first step, which you've already...

    Asked by user6644468 on via web

    2 educator answers.

  • Science
    The molecules of air inside of an inflated balloon are very far apart and moving rapidly. They collide with other molecules and with the inside surface of the balloon. The volume of the balloon...

    Asked by yanarose28 on via web

    1 educator answer.

  • Science
    Substances can be classified as either element, compound or mixtures. Elements are the purest form of substances, since they contain only one type of atoms. Examples of elements include, iron,...

    Asked by baublitzj21 on via web

    1 educator answer.

  • Science
    Glucose is an organic compound with mixed functions (carbonyl and more hydroxyl groups). The elemental analysis shows that glucose is an hexose `C_6H_12O_6` and the analysis of functional groups...

    Asked by yensym23 on via web

    1 educator answer.

  • Science
    Reflection and refraction are both behaviors of waves , such as light and sound waves. To “reflect” means to “bounce off of”. Reflection of light occurs the best off of smooth, hard, and...

    Asked by mollykate142 on via web

    1 educator answer.

  • Science
    Many differences exist when looking at the characteristics and functions of both slow and fast twitch skeletal muscle fibers. Classically, muscle fibers are broken into four subtypes. Slow twitch...

    Asked by user2077500 on via web

    1 educator answer.

  • Science
    Permeability refers to the ability of a surface to allow the transport of particles across it. A membrane is termed permeable if it allows the transport of molecules across it. A semi-permeable...

    Asked by mahzineafroz on via web

    1 educator answer.

  • Science
    An example of a food chain has been provided in this question. The components of this food chain are seeds, mice and fox. Here, seeds are the primary food, which is eaten by the mice, who in turn...

    Asked by asia77 on via web

    1 educator answer.

  • Science
    We can solve this by using the equation of motion. `s = ut + 1/2 at^2` where s is the distance traveled, u is the initial velocity, t is the time duration and a is the acceleration. In this case,...

    Asked by madeleinevillalon on via web

    1 educator answer.

  • Science
    When Thorium-240 decays to radium-226 it emits an alpha particle and loses 4 mass units. 15 grams of radium-226 resulted from the decay of this amount of thorium-230: (15g)(230/226) = 15.26 g Since...

    Asked by bellavivi1921 on via web

    1 educator answer.

  • Science
    Change is a difference from the current state. For example, water changes to steam, when it is boiled and hence has a change of state from liquid to gas. When talking about change in physics or...

    Asked by panchitolara18 on via web

    1 educator answer.

  • Science
    I can't see the last choice on your sheet but I will assume it is J) animals A and C because that would be the correct answer. Choice A is an insect, and choice C is a turtle. They both exhibit...

    Asked by cch4202 on via web

    1 educator answer.

  • Science
    During mitosis, a cell divides into two identical cells referred to as daughter cells. In order for both cells to be fully functional and to be able to mature, they each need a complete set of DNA....

    Asked by chino6195 on via web

    1 educator answer.

  • Science
    According to the Guinness Book of World Records, the Bonobos are slightly more similar to humans, genetically, than Chimpanzees: "Bonobos, primates similar to chimpanzees, which live only in the...

    Asked by samantharulez on via web

    1 educator answer.

  • Science
    Our universe is very, very, very big and the common units of distance measurement (such as meter, kilometer, miles, etc.) will simply not suffice for measuring distances in our vast universe. For...

    Asked by angiecastro1707 on via web

    1 educator answer.

  • Science
    Radiation is energy that travels through and is transferred by waves. Non-ionizing radiation and ionizing radiation are two types of radiations. Non-ionizing radiation has less energy and,...

    Asked by enotes on via web

    1 educator answer.

  • Science
    When a body slows down, its speed decreases. If it is traveling in a straight line, like a train on a straight track, we can also say that its velocity is decreasing. Acceleration is the rate of...

    Asked by enotes on via web

    1 educator answer.

  • Science
    DNA replication occurs in the nucleus of eukaryotic cell. By definition, prokaryotic cells do not have nuclei. Therefore, DNA replication occurs in the cytoplasm of a prokaryotic cell. DNA...

    Asked by nilloufar1382 on via web

    1 educator answer.

  • Science
    If the driver applies brakes, the vehicle will accelerate and ultimately stop. However, the distance that it travels before stopping (even after the application of the brakes) is known as the...

    Asked by mrdarwinlefebvre on via web

    1 educator answer.

  • Science
    The fossil record is considered to be incomplete for a number of reasons. The primary factor in why the record is considered to be incomplete has to do with preservation and the science of...

    Asked by confusedstudent16 on via web

    2 educator answers.

  • Science
    The nitrogen cycle shows how this important element circulates from the living component of the ecosystem which comprises all of its organisms, to the non-living surroundings and back again....

    Asked by user7692605 on via web

    1 educator answer.

  • Science
    The terms covalent and molecular are often used interchangeably to describe the same type of substance. However, there is a distinction between the two. The term covalent refers to a type of...

    Asked by enotes on via web

    1 educator answer.

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