In what phase does water have its highest specific heat

If the chemical properties of a substance remain unchanged and appearance or shape of a substance changes it is called a ?

Under the action of a constant force an object accelerates at 7.8 m/s2. what will the acceleration be if (a) the force is halved? (b) the object's mass is halved? (c) the force and the object's mass are both halved? (d) the force is halved and the object's mass is doubled?

Explain why you think this diagram shows what happened to the carbon in the biodome.