What kind of thermal transfer 1.conduction 2.convective 3.radiation from the sun?

Radiation

Explanation:
Radiation is the type of heat transfer through the electromagnetic waves. Transfer of heat by radiation can occur in space/vacuum as in between the sun and the earth

On the other hand:
Conduction is the transfer of heat through touching on objects while convection is the transfer of heat as a result of moving currents in liquids or gases.

Hope this helps :)

Answer:   [a]:   "slate" .

Answer (d) the universe had cooled enough for atoms to combine, protons and neutrons were too far apart to form nuclei;