12. a sound wave is modeled with the equation y = 1/4 cos 2pi/3 θ. a. find the period. explain your method. b. find the amplitude. explain your method.,

Amanda went into the grocery business starting with five stores. after one year, she opened two more stores. after two years, she opened two more stores than the previous year. if amanda expands her grocery business following the same pattern, which of the following graphs represents the number of stores she will own over time?

Find the condition that the zeros of the polynomial f(x) = x^3+3px^2+3px+r may be in a.p.

Use the given information to determine the exact trigonometric value.