What is chromatography used for? Select all that apply. ] dissolving substances
separating liquids in a mixture
crystallizing substances
separating gases in a mixture

Separating liquids in a mixture

Separating gases in a mixture

Explanation:

Chromatography is the separation of a mixture by passing it in solution or gas through a medium where the components move at different rates.

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.

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