After turning over 10 cards, there are 42 cards remaining.
The 10th card is a king and the first face card to appear.; but we don't know which king.
If it's the king of spades, the probability that the next card is the king of spades is 0.
If it's not the king of spades, the probability that the next card is the king of spades is 1/42.
(The probability that the next card is a king is 3/42.)
The probability that the next card is the queen of spades is 1/42.
(The probability that the next card is a queen is 4/42.)