In january, the depth of a lake was 1,174 feet. in august, the depth of the lake was 763.1 feet. what is the percentage decrease of the depth of the lake from january to august?

Which matrix can be multiplied to the left of a vector matrix to get a new vector matrix ?

Cam bought some used books for $4.95. he paid $0.50 each for some books and $0.35 each for the others. he bought fewer than 8 books at each price. how many books did cam buy?

Jackie purchased 3 bottles of water and 2 cups of coffee for the family for $7.35. ryan bought 4 bottles of water and 1 cup of coffee for his family for 7.15. how much does each bottle of water cost? how much does each cup of coffee cost?