a) Black and Face Cards: Spades - Ace, King, Queen, Jack (4 cards)
Clubs - Ace, King, Queen, Jack (4 cards)
Total of 8 cards
So Probability is 8/52 but you will simplify the fraction.
b) Black or Face Cards : Total Black - 26 cards
Total Face Cards - 16
Total Black + Total Face = 42
But you don't want to double count so you take out Black and Face (8)
42 - 8 = 34
So Probability is 34/52 but you will simplify the fraction.