How much heat is needed to raise the temperature of 9g of water by 18oc?

Why are graphs useful when interpreting data

Two objects of different mass start from rest, are pulled by the same magnitude net force, and are moved through the same distance. the work done on object 1 is 900 j. after the force has pulled each object, object 1 moves twice as fast as object 2. how much work is done on object 2?

This is for my 8th grade science class, i really don’t understand. can someone me? , lol.