How much energy is required to vaporize 234.5 g of water

co2reflects heat radiation back to earth buning coal and oil emits co2 globe warms

when two balls of the different masses are dropped from equal height, they reach the ground at the same time .this is because they experience the same acceleration.

the acceleration is independent of mass.

thus when they are dropped they will always maintain the same velocity and travel the same distance (neglect air resistance of course) at the same time.