A 1.00 g sample of naphthalene (C10H8) contains 0.562 g of hydrogen. What is the mass percent of carbon in the compound? A.
10.079%
B.
12.01%
C.
43.8%
D.
50.02%
E.
56.2%

43.8%

Explanation:

Hydrogen+Carbon=1.00g

so carbon =1-0.562=0.438g

Mass percent=(0.438÷1)×100%

=43.8%

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.