PLEASE HELP ME Which modes of heat transfer require a medium? Which does not? Explain why a medium is/is not
needed for each response.

Conduction and convection requires Modes of transfer of heat ! Radiation doesn't require any medium !!

In terms of heat transfer, radiation is the emission of thermal energy in the form of infrared waves. ... Since heat is carried by electromagnetic waves, it does not need a physical medium to transfer it. Instead it radiates through space - this is how the Earth is heated by the Sun despite space being a vacuum

to know more about conduction and convection you can take the help of internet search

the answer would be c. motion and direction

i hope this : )