l. (1 point) A woman at a point A on the shore of a circular lake with radius r = 4 wants to arrive at the point C diametrically opposite A on the other side of the lake in the shortest possible time. She can walk at the rate of 10mph and row a boat at 5mph. E What is the shortest amount of time it would take her to reach point C? hours What is the longest amount of time it would take her to teach point C following a path like the path in the gure? hours 2. (1 point) The FM radio station KAlVIB broadcast from an antennae atop a 160 meter tall radio tower at a frequency of 85 MHz with a total radiated power of 30 kilowatts. Neighbors have complained about problems they attribute to excessive ra- diation from the tower, but the city engineer who measured the radiation level near the base of the tower found it to be well be- low the accepted standard. You have been hired by the HOA to assess the engineer's report. You know a few things about elec- tromagnetic radiation and therefore conclude that we must nd the optimum place on the ground to measure the maximum ra- diation emitted from the antennae. From your extensive knowl- edge in physics, you know that the intensity of radiation, I, is given by the formula: - 2 I : 10 sm (9) 327B 1'2 where P is the power output, r is the distance from the top of the tower to the point on the ground, and 9 is the angle measured from the tower to r. Find the distance R from the base of the tower to the optimum location for taking the radiation reading. m What is the maximum radiation reading from the ground? kW _2' m If the city code requires that electromagnetic radiation be un- der 200 microwatts per square meter, is this antennae operating within city code? Yes or No