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**Ideasman** Suppose there are all these bubbles, where each bubble is shaped as a different type of surface. One of the bubbles is shaped as a circular cylinder, and it will keep that general shape over time, although the height increases at a rate of 3 cm/sec while the radius will decrease at a rate of 1 cm/sec (and when the bubble gets thin enough it will eventually pop).

1.) What rate is the volume, V, of this bubble changing when it is 10 cm high and 6 cm across at the bottom?

2.) What rate is the surface area of the bubble changing at the same instant?