Work out the size of one interior angle of a regular 10 sided shape (decagon)

Which of the choices shown could be used to prove that aacp=abcp ?

The trigonometric ratios sine and secant are reciprocals of each other

The average daily maximum temperature for laura’s hometown can be modeled by the function f(x)=4.5sin(πx/6)+11.8 , where f(x) is the temperature in °c and x is the month. x = 0 corresponds to january.what is the average daily maximum temperature in may? round to the nearest tenth of a degree if needed.use 3.14 for π .