Answer:

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Step-by-step explanation:
Arithmetic sequence

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First step, find its difference



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So, we get


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Finally, Let's find the 75th term




Integer??? Idk I'm sorry....
5/2 * 6 = 15
h/6 * 6 = h
so
h = 15
The school is 15ft tall
The concept that is useful in order to answer this item is the concept of ratio and proportion. Let x be the height of the rock from the ground. We use the equation below to answer.
5.5 ft / 18 ft = x ft / 209.5 ft
The value of x from the equation is 64 ft. Thus, they will be needing approximately 64 ft of rope.