What properties of radio waves makes them suitable for sending signals in mountainous regions?

one of the property of radio waves is that they have long wavelength. due to their long wavelength , they undergo diffraction around the mountains and thus the waves spread around the mountain. this makes them eligible to be used for  long distance communication. they can coded and decoded also . that is why they are used in television and radio system

the temperature and the pressure affect solubility. temperature affects by changing the properties of the solvent. the increase in pressure increases solubility, the decrease in pressure decreases solubility.

1/0.14nm = 10^10/1.4 a lot