A Retail Sporting Goods Store Estimates That Weekly Sales and Weekly

Multiple Choice

A retail sporting goods store estimates that weekly sales and weekly advertising costs are related by the equation $S = 2290 + 90 x + 0.35 x ^ { 2 }$ . The current weekly advertising costs are $1500, and these costs are increasing at a rate of $140 per week. Find the current rate of change of weekly sales.

A) 159,600 dollars per week
B) 161,890 dollars per week
C) 88,390 dollars per week
D) 86,100 dollars per week
E) 802,390 dollars per week