Janis owns and operates a store in a country experiencing a high rate of inflation. in order to prevent the value of money in her cash register from falling too quickly, janis sends an employee to the bank four times per day to make deposits in a interest-bearing account that protects the store's revenues from the effects of inflation. this is an example of the (menu costs/ unit of account costs/ shoesleather costs) of inflation. pick one

When a company produces and sells x thousand units per week, its total weekly profit is p thousand dollars, where upper p equals startfraction 800 x over 100 plus x squared endfraction . the production level at t weeks from the present is x equals 4 plus 2 t. find the marginal profit, startfraction dp over dx endfraction and the time rate of change of profit, startfraction dp over dt endfraction . how fast (with respect of time) are profits changing when tequals8?