A card is taken form a deck of cards and then replaced. After the deck is shuffled a second card is taken from the deck. Calculate the following probabilities

a. Both cards are diamonts or both are hearts

P(A or B) = P(A) + P(B) - P(AandB)

P(A) should be= P(1st card diamand)X P(2nd card is diamand) = 13/26 x13/26??

P(B) should be = P(1st card hearts) X P(2nd card hearts) 13/26 X 13/26??

P(A and B) ??

b. Both cards are black or both cards ar hearts

c. Both cards are hearts and both card are face cards.