Can u help me out please?

Find the common ratio of the sequence. -4, 8, -16, 32, a: -12b: -2c: 12d: -1/-2

Ineed with question three. i don't understand how i'm supposed to achieve 3 marks.

If you do this you are getting 20+ points so can you hurry plsphil is riding his bike. he rides 29 miles in 2 hours, 43.5 miles in 3 hours, and 58 miles in 4 hours. find the constant of proportionality and write an equation to describe the situation. let x represent the number of hours.