Suppose about 400,000 people live in an areas of 160 square miles. What is the best estimate for the population density?

Ijust need these 2 questions answered (the second pic is just confirmation i'm not confident in that answer)

Using the figure below, select the two pairs of alternate interior angles.a: point 1 and point 4 b : point 2 and point 3 c: point 6 and point 6d: point 5 and point 7

Me i’m stuck on all these questions besides the two bottom ones