Rectangle is inscribed in a circle of radius 5 inches. If the length of the rectangle is decreasing at the rate of 3 inches per second, what is the rate of change of the area at the instant when the length is 4 inches?

Aparticular telephone number is used to receive both voice calls and fax messages. suppose that 25% of the incoming calls involve fax messages, and consider a sample of 25 incoming calls. (a) what is the expected number of calls among the 25 that involve a fax message?