Which ions are most abundant in water ?

In a given chemical reaction, the energy of the products is greater than the energy of the reactants. which statement is true for this reaction?

Ahot-air balloonist, rising vertically with a constant speed of 5.00 m/s releases a sandbag at the instant the balloon is 40.0 m above the ground. after it is released, the sandbag encounters no appreciable air drag. compute the velocity of the sandbag at 0.250 s after its release.

Could someone . i have tried to solve myself but my calculation is off