Let acceration of the bike is a m/sec^2.
Bike started from rest so its initial speed will zero i.e.
It reaches at a speed of 7.10 m/s i.e final speed v= 7.10 m/s
In reaching speed 7.10 m/s ,it covered distance 35.4 m.
Apply equation of motion which relates u ,v ,a and s
`(7.10)^2=(0)^2+2 a (35.4)`
So acceleration of the bike which started from rest , reaches at speed of 7.10 m/s by travelling distance 35.4 m will be 0.712 m/sec^2.