Answers: A, C, D
Explanation: Let (x-3)=0. x then equals 3. Substitute f(3) into each equation, and the ones which equal 0 are the answer.
D/H = 0.25
18/H = 0.25/1
Cross multiply and solve for H
True because that's the statement factor . There fore it's true

Hope you could get an idea from here.
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