What elements are present in this formula? : c7h8n4o2, how many atoms of each element are in this molecule? what patterns do you notice between these elements on the periodic table?

carbon, hydrogen, nitrogen, and oxygen. the number infront is how many of each element there are, they are increasing and decreasing

1) 21 atoms are present: seven of carbon, eight of hydrogen, four of nitrogen and two of oxygen.

2) They all belong to different groups.

Explanation:

The following elements are present

carbon

hydrogen

oxygen

nitrogen.

The number of atoms of each element in the molecular formula is represented by the subscript.

The formula given is:C₇H₈N₄O₂

C₇ : It means seven atoms of carbon

H₈: It means eight atoms of hydrogen

N₄: It means four atoms of nitrogen

O₂: It means two atoms of oxygen.

The pattern is that all the elements belong to different groups in the periodic table.

Apart from hydrogen all other three elements are of same period also.

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.