Help quick! Don’t have that much left

Angela took a general public aptitude test and scored in the 88th percentile for aptitude in accounting. what percentage of the scores were at or below her score?

If x+y+z=0 what is the value of [tex] {x}^{3} + {y}^{3} + {z}^{3} [/tex]

The power generated by an electrical circuit (in watts) as a function of its current c (in amperes) is modeled by p(c)= -15c(c-8) what current will produce the maximum power?