When communicating with apollo astronauts, there is approximately a 1.3 second delay in one-way communication. this is because

a)
space is a vacuum.

b)
the moon has virtually no atmosphere.

c)
radio waves travel at a speed of 186,000 miles/s.

d)
of the scattering of electromagnetic waves in space.

Radio waves travel at a speed of 186,00 miles/s

Change in speed or direction : )

You would be correct, boiling water does disinfect contamination.    the property of disinfecting means to kill  germs, bacteria and other pathogens or contamination  that might cause an infection or cause a person to become sickly. a couple methods of disinfecting are using soap, other cleaning supplies or by simply "boiling" the contaminate.  the reason why boiling water disinfects certain attributes is because some cells cannot survive the heat and pressure.