A radar for tracking aircraft broadcasts a 12 GHz microwave beam from a 2.0 m diameter circular radar antenna. From a wave perspective, the antenna is a circular aperture through which the microwaves diffract.
Part A) What is the diameter of the radar beam at a distance of 30 km?
Part B) If the antenna emits 100 kW of power, what is the average microwave intensity at 30 km? (In W/m^2)