Can someone help me please? I'll give brainlest for correct answer​

Dawn is selling her mp3 player for 3 4 of the original price. the original price for the mp3 player was $40. how much is she selling her mp3 player for?

For a function f(x), a) if f(7) = 22 then f^-1(22) = b) f^-1(f(c)) =

Emmanuel added 888 links per minute to his chain mail. allesia started 202020 minutes after emmanuel and added 131313 links per minute to her chain mail. how long had emmanuel worked when allesia caught up to him, and how many links had he added?