Assume that x=x(t) and y=y(t). Let y=x2+2 and dtdx=3 when x=1. Find dtdy when x=1 Assume that x=x(t) and y=y(t). Find dtdx, using the following information. x2+y2=0.73;dtdy=2whenx=0.3andy=0.8 Suppose that for a company manufacturing calculators, the cost, revenue, and profit equations are given by C=70,000+20x,R=300x20x2,P=RC where the production output in 1 week is x calculators. If production is increasing at a rate of 400 calculators per week when production output is 6,000 calculators. Find the rate of increase (decrease) in cost, revenue, and profit. A) Costs are at the rate of $ per week at this production level. (Simplify your answer.) A retail store estimates that weekly sales s and weekly advertising costs x (both in dollars) are related by s=80,00020,000e0.0004x. The current weekly advertising costs are $2,500, and these costs are increasing at a rate of $600 per week. Find the current rate of change of sales. The current rate of change of sales is per week. (Round to the nearest dollar as needed.)