Guys please help me i dont know eich to chose

The lines shown below are parallel. if the green line has a slope of -1, what is the slope of the red line

*let m∠cob = 50°30’, m∠aob = 70° and m∠aoc = 20°30’. could point c be in the interior of ∠aob? why? a. point c could be the interior of aob but it is not the only case b. point c is the interior of aob c. point c is not the interior of aob d. the given is not possible for the plane geometry answer

Apackage of five erasers cost 0. $.39 at this rate how many how much would 60 erasers cost in dollars and cents