Answer:
That's simply because any electromagnetic wave longer than a microwave is called a radio wave. Microwaves: Obviously used for cooking in microwave ovens, but also for transmitting information in radar equipment. Microwaves are like short-wavelength radio waves. Typical size: 15cm (the length of a pencil).
Distance traveled by the ball is given by

here we know that
speed = 20 m/s
times = 0.25 s
now we have


so ball will travel 5 m distance in the given interval of time
Wave speed = frequency * wavelength
Wave speed = 4 * 25
Wave speed = 100 m/s
m=23.8kg a=8.97m/s^2 Fnet=? Fnet=ma=(23.8kg)(8.97m/s^2)=213.486N