PLEASEE HELPP MEEE WITH NUMBERSSS 6 AND 7

Which of the expressions (on the photo document i inserted) together represent all solutions to the following equation? 8cos(12x)+4=-4 *the answer should be in degrees.* > i would like for someone to explain the process to find the solutions for this.

Parabolas y=−2x^2 and y=2x^2 +k intersect at points a and b that are in the third and the fourth quadrants respectively. find k if length of the segment ab is 5.

Which of the following statements are true about the graph of f (x) = 1/4 coz ( x + π/3) - 1? select two of the following that apply.