HELP PLS!! according to the rational root theorem, -2/5 is a potential rational root of which function?

If value of cos330° is √3/2 then find tan165°.

Si el duplo del mayor de dos numeros se divide entre el el triplo del menor, el cocient es 1 y el residuo 3, y si 8 veces el menor se divide por el mayor, el cociente es 5 y el residuo 1

Harold wrote this equation to model the level of water in a pool over time. the variable x represents time in hours. f(x) = 3,500 - 225x which statements about the situation are true? check all that apply. the water level is rising. the water level is falling. the initial level of water in the pool was 3,500 units. the initial level of water in the pool was 225 units. the pool was empty after 14 hours. the water was 2,600 units high after 4 hours.