NO FILES PLZ HELP When a solid produced by a chemical reaction separates from the solution it is called...

a precipitate.
a molecule.
b. a reactant.
d. the mass of the product.

a. Precipitate

Explanation:

solids can precipitate out of the solution and be left over after the reaction. reactants are incorrect because they are reacted to cause the reaction. b and d are also irrelevant terms.

a: 45.9 meters

b: 4.29 seconds

step-by-step explanation:

a: h(t)=1/2(-9.8)(3)^2+0(3)+90

h(t)=-4.9(3)^2+90

h(t)=-44.1+90

h(t)=45.9 meters

b: 0=1/2(-9.8)(t^2)+0t+90

0=-4.9t^2+90

-90=-4.9t^2

18.37=t^2

t=4.29 seconds

in the second question, the numbers aren't exact, but they're a close approximation.