> 2A-Practice Final-Sample1 SOLUTI... Final-Sample1 SOLUTIONS.pdf ctice Final-Sample1 SOLUTIONS.pdf (17.4 MB) 8. (10 points) A pebble is dropped into a calm pond, causing ripples in the form of concentric circles. The radius r of the outer ripple is increasing at a constant rate of 2 ft/sec. When the total area of the disturbed water is 167 square feet, at what rate is the total area of the disturbed water changing? Remember to include units. A = Trz dA_ d ( Tr ? ) = Td (r? ) = TT. 2r dr DD DII O G K F10 Q F9 F8 F7 F5 F6