Find the value of the trigonometric ratio. make sure to simplify the fraction if needed.

Which sum or difference identity would you use to verify that cos (180° - ∅) = -cos ∅? a. sin (α -β) = sin α cos β – cos α sin β b. cos (α -β) = cos α cos β – sin α sin β c. cos (α -β) = cos α cos β + sin α sin β d. sin (α + β) = sin α cos β + cos α sin β

Calculate the missing value. round the answer to on decimal place. start with 70, increase it by 21%, and end up with

With number 11 ( show how you got the answer)