The word "Que" is important here as it means "What." The verb ser can be used here to represent "is." Given both of these, your opening translation will begin, "Que es..." This is a fairly important prefix to most questions in the Spanish language. "Que es la pregunta" literally translates to "What is the question?" Another example of where the prefix is used is in "Que es la problema," asking what a specific problem is. In this light, one can see how the question is constructed using "Que es" as the opening. The word "salary" can be seen in many different lights. "Dinero" means "money," and while this could work, it does not have the same effect as the word "salary." I can see two vocabulary words working well here. "Salario" means salary as in wages, as does "sueldo." Either one might be appropriate here, so your final question would read as "Que es el salario" or "Que es el sueldo." Either way, I believe you are constructing a translation of the sentence, "What is the salary?" The prefix of "Que es" sets it up with the finding of the term for "salary" ending it.