A pebble is dropped into a calm pond, causing ripples in the form of concentric circles. The radius (in feet) of the outer ripple is , wheretis the time in seconds after the pebble strikes the water. The area of the circle is given by the function 

style="font-size:12pt;vertical-align:middle;" />. Find and interpret .

?



A. ;  represents the area of the circle  at time t.
B. ;  represents the area of the circle  at time t.
C. ;  represents the area of the circle  at time t.
D. ;  represents the area of the circle at time t.
E. ;  represents the area of the circle  at time t.

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Answer: D

Mathematics

Solve the problem.Find a formula for the area of the shaded grey region and express it in factored form.9x1

A. 9x - 1 B. (9x + 1)(9x - 1) C. (9x - 1)(9x - 1) D. (x + 9)(x - 9)

Write the word name for the number.3072

A. Three thousand, seventy-two B. Three hundred thousand, seventy-two C. Three million, seventy-two D. Thirty thousand, seventy-two

Solve the equation. Round your answer to three decimal places.logx(3.6) = 4.6

A. 1.528 B. 1.321 C. 243.18 D. 362.236

Is this the graph of a function having the following properties?(I) f'(x) < 0 for all x(II)f''(x) > 0 for all x < 0 (III)(0, 1) is a point on the graphEnter your answer as just "yes" or "no" (lower case).

Fill in the blank(s) with the appropriate word(s).