In terms of its radius 
, the volume of the balloon is
The diameter 
is twice the radius, so that in terms of its diameters, the balloon's volume is given by
Differentiate both sides with respect to time 
:
The diameter increases at a rate of 
. When the diameter is 
, we have
or about 23,562 cc/min (where cc = cubic centimeters)
To determine the Earnings of Shelley last week, we need to make relations with the values that are given. We let x as the total amount she earned last week by x and y as the additional amount she earned this week We do as follows:
20% additional amount she earned this week = y / 72 - y
y = $ 12
x = 72 - 12 = $60 total earnings last week
Arrange them first
4,5,5,6,10,11,12,13
These are 8 numbers.we will divide the sum of middle 2 numbees on 2.
6+10=16÷2
8..median
140a/35s=4a/s
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