Which of the following chemical reactions is an oxidation-reduction reaction?
a. cuso4 + bacl2 yields baso4 + cucl2
b. pb(no3)2 + 2nacl yields pbcl2 + 2nano3
c. n2 + 3h2 yields 2nh3
d. k2so4 + bacl2 baso4 + 2kcl

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 earth would become to overheated and everything alive on it will eventually die from overheating. plants will eventually die as well, water will evaporate, and it will be nothing but a hot planet without anything living on it.