3. Shortwave radio is broadcast between 3.50 and 29.7 MHz, To what range

of wavelengths does this correspond? Why do you suppose this part of

the spectrum is called shortwave radio?

The wavelengths are 85.71m and 10.10m

They're called shortwave radio because their range are smaller compared to what's obtainable in radio waves which can be high as much as 1000m

Explanation:

Using the relationship y = c / f

Where y represents the greek alphabet lambda is the wavelength

C = speed of light = 3.0 * 10⁸ m/s

f = frequency of the wave

1. y = c / f = 3.0 * 10⁸ / 3.50 * 10⁶ = 85. 71m

2 y = c / f = 3.0 * 10⁸ / 29.7 * 10⁶ = 10.10 m

From the above calculation, none of the wavelength met the usual 1000m for radio wave hence they're referred to as shortwave radio.