Write these ratios in simplest terms a, 10:15 b, 72:3 c, 20:5 d, 40:5 e, 12:6 f, 60:80 g, 40:4 h, 500:5 I, 600:10 j, 60:3

Barbara's piano instructors house is 7 1/8 miles from her house. after biking for 1 3/4 miles she stops to rest how much longer does she need to bike to reach her instructor's house

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

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.