Need help ASAP giving 100 points Show ur work plz

1. what are the missing reasons in the proof 2. it's in the second picture and 3

Astandard deck of cards contains 52 cards. one card is selected from the deck. (a) compute the probability of randomly selecting a seven or king. (b) compute the probability of randomly selecting a seven or king or jack. (c) compute the probability of randomly selecting a queen or spade.

The jewelry store is having a sale. necklaces that were regularly priced at $23.50 are on sale for $18.80. what is the percentage of decrease in the price of necklaces?