Questions attached to the link

Ineed ! the person who answers and shows their work on they got the answer first will be marked the !

Scarlet bought three pairs of sunglasses and two shirts for $81 and paula bought one pair of sunglasses and five shirts for $105 what is the cost of one pair of sunglasses and one shirt?

Due to a packaging error, 4 cans labeled diet soda were accidentally filled with regular soda and placed in a 12 pack carton of diet soda. two cans were randomly selected from this 12 pack. what is the probability that both cans were regular soda?