Which of the following is NOT a molecular formula?
F2
Na2SO4
H2O
CO2

Hello there! :) All of these are molecular formulas but F2.

Explanation:

F2 goes by the name flourine and is not F2 in it's chemical makeup. Na2SO4 is also called Sodium Sulfate and is a molecular formula. Everyone knows what H2O is, the molecular formula for water and lastly CO2 is carbon dioxide. Hope this helps!

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.