Help me please ASAP on the math nation test yourself

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.

1. are the corresponding angles congruent 2. find the ratios of the corresponding sides 3. is triangle jkl congruent to triangle rst? if so what is the scale factor

Find the arc length of the semicircle. 7the grade