If 0 < f ≤ 90 and cos(22f − 1) = sin(7f + 4), what is the value of f?

Tanya has $42 to spend at the dolphin island store. tshirts sell for $7 each and a pair of sunglases sells for $6.tanya buys 3 tshirts. how many pairs of sunglases can she buys with the amount of money she has left

In july, the average temperature in one us city was 29°c. by december, the average temperature had fallen by 29°c. explain why the average temperature in december was 0°c.

Step by step explanation pls for 10 pts the length of a rectangular board is 3 feet less than twice its width. a second rectangular board is such that each of its dimensions is the reciprocal of the corresponding dimensions of the first rectangular board. if the perimeter of the second board is one-fifth the perimeter of the first, what is the perimeter of the first rectangular board?