I need help in figuring out the answers to these two questions.
1. A vertical circular cuylinder has radius r feet and height h feet. If the height and radius both increase at the constant rate of 2ft/sec, then the rate, in square feet per second, at which the lateral surface area increases is: Answer Choices: A.4(pie)r B.2pie(r+h) C. 4pie(r + h) D. 4(pie)(r)(h) E. 4(Pie)(h)
2.Two cars are traveling along perpendicular roads, car A at 40 mi/hr and car B at 60 mi/hr. At noon when car A reaches the intersection, car B is 90 mi away, and moving toward at it. At 1 P.M. the distance between cars is changing, in miles per hour, at the rate of: Answer Choices: A. -40 B. 68 C.4 D.-4 E. 40
Thank you so much in reading this and helping me out! Its greatly appreciated!!
:Erin
2007-12-05
03:36:06
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2 answers
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asked by
Anonymous
in
Mathematics