How much would the kinetic energy of an object decrease if you reduced its mass in half but not its speed?

In half it would go twice as far but the effect of lost kinetic energy is lessened.

( I could be wrong)

the atomic mass is the bottom number on the element.

-steel jelly

answer is: naturally occurring solid, inorganic compound or element is mineral.

minerals usually have crystalline form, that means than crystal constituents (atoms, molecules or ions) are arranged in a highly ordered microscopic structure, forming a crystal lattice that extends in all directions.

for example magnetite is a mineral of iron oxide (fe₂o₃).

calcite is a carbonate mineral and the most stable polymorph of calcium carbonate (caco₃).

dolomite is an   carbonate mineral composed of calcium magnesium carbonate (camg(co₃)₂).