Scientific notation.

23.1 x 10^11

Explanation:

(4.2x5.5) x (10^9x10^2)

23.1 x 10^11   (Add the exponents, and multiply the decimals.)

I hope this helped! :)

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.

the electron configuration that you gave me has 16 electrons ergo it has 16 protons ergo it is the element sulfur.