Question 1177976
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Air is pumped into a spherical balloon at the rate of 20 cm s-1  When the radius of the balloon is 10 cm, calculate 
(a) The rate of change of the radius
(b) The rate of change of the surface area
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The rate of pumping air into the balloon CAN NOT be measured in  cm/s.



It is not an appropriate unit.



Revise your post.



As worded,  it  MAKES  no  SENSE.