Question: AIR PURIFICATION To study the effectiveness of air purifiers in removing smoke, engineers ran each purifier in a smokefilled 10-ft × 20-ft room. In the accompanying figure, the function f gives the rate of change of the smoke level/ minute, t min after the start of the test, when a brand A purifier is used. The function t gives the rate of change of the smoke level/minute when a brand B purifier is used.
a. Give an interpretation of the area of the region S.
b. Find an expression for the area of S in terms of a definite integral involving f and g.
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