Please help!! I'm in summer school and I can't fail

Terri makes a quilt using three sizes of fabric squares the side lenght of each fabric square is the square root of the area

The swimming pool is open when the high temperature is higher than 20∘c. lainey tried to swim on monday and thursday (which was 3 days later). the pool was open on monday, but it was closed on thursday. the high temperature was 30∘c on monday, but decreased at a constant rate in the next 3 days. write an inequality to determine the rate of temperature decrease in degrees celsius per day, d, from monday to thursday.

Express the following as a function of a single angle. cos(60) cos(-20) - sin(60) sin(-20)