A retail store estimates that weekly sales s and weekly advertising costs x (both in dollars) are related by s =70,000-40,000e^0.0005x. The current weekly advertising costs are $2,000 and these costs are increasing at a rate of $300 per week. Find the current rate of change of sales. round to the nearest dollar as needed A manufacturer of handcrafted wine racks has determined that the cost to produce x units per month is given by C=0.3x210,000. How fast is the cost per month changing when production is changing at the rate of 13 units per month and the production level is 70 units?Costs are at the rate of $ per month at this production level.(Round to the nearest dollar as needed.)The price p(in dollars) and demand x for wireless headphones are related by x=8,000-0.1p2. The current price of $110 is decreasing at a rate $7 per week. Find the associated revenue function R(p) and the rate of change (in dollars per week) of revenue.R(p)=