In conventional television, signals are broadcast from towers to home receivers. Even when a receiver is not in direct view of a tower because of a hill or building, it can still intercept a signal if the signal diffracts enough around the obstacle, into the obstacle's "shadow region". Current television signals have a wavelength of about 50 cm, but future digital television signals that are to be transmitted from towers will have a wavelength of about 10 mm. Assume that a signal passes through an opening of 4.23 m width between two adjacent buildings. What is the angular spread of the central diffraction maximum (out to the first minimum) for wavelengths of:

(a) 50 cm

(b) 10 mm