Radiation transfers thermal energy from the sun to earth by electromagnetic waves. Electromagnetic waves transfer energy with or without matter. Thermal energy will flow from the to the .
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Thermal energy will flow from a warmer substance to a cooler substance

The problem here is that according to aufbau principle before 3d orbital 4s subshell comes.after filling 3p orbital with electrons you have 4 electrons left, you place two in 4s with opposite spin and the other two in 3d in any of its two orbitals of total five orbitals with the same spin.