Answer: Choice D) I and III
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We can rule out equation II because it simplifies to f(n) = 44n-20 which means the height is growing by 44 inches each day, instead of 24
Equation I is true because plugging n = 0 leads to f(n) = 20 which is the proper starting height. Plugging in n = 1 leads to f(n) = 44 (indicating a growth of 24 inches over that first day).
Equation III is true because we start off at 20 inches when it says f(0) = 20, which is the initial value to base the recursion off of. Then we add on 24 each time on the recursive step. Writing f(n) = f(n-1)+24 means "add 24 to the previous term, the (n-1)st term, to get the next term or nth term"
So together Equation I and Equation III are true which is why choice D is the final answer