A) find the average rate of change of the area of a circle with respect to its radius r as r changes from 4 to each of the following.

(i) 4 to 5

(ii) 4 to 4.5

(iii) 4 to 4.1

(b) find the instantaneous rate of change when r = 4.

a'(4) =

Nine more than four times a number is the same as one less than twice the number. find the number?

Twenty points. suppose that one doll house uses the 1 inch scale, meaning that 1 inch on the doll house corresponds to 1/2 foot for life-sized objects. if the doll house is 108 inches wide, what is the width of the full-sized house that it's modeled after? in inches and feet

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