Describe the spin of carbon-14's valence electrons and explain how you came about your answer.

we have to know the spin of valence electrons of carbon-14

There are four unpaired electron which are called as valence electron also. The spin of the four unpaired electron is either upfilled or down filled.

The ground state electronic configuration of C-atom is 1s²2s²2p² and one electron from 2s orbital gets excited to 2p orbital. The elctronic configuration in excited state is 1s²2s¹2p³.

The electron jumps because half-filled orbitals are more stable. Exchange energy is less than pairing energy.