Abackyard swimming pool holds 165 cubic yards (yd3) of water. what is the weight of the water in pounds?

Oxygen and hydrogen gas are at the same temperature t.what is the ratio of kinetic energies of oxygen molecule and hydrogen molecule if oxygen is 16 times heavier than hydrogen.

5g of ammonium nitrate was dissolved in 60g of water in an insulated container. the temperature at the start of the reaction was 23.0°c and at the end it was 19.0°c. calculate the energy absorbed by the reaction.

What is the weight of a feather (mass = 0.0001 kg) that floats through earth's and the moon's atmospheres?