No files pls. Im not the best at the mad, so can i have the answer and the explanation. (iim resting out of 6th grade)

Atrain leaves little? rock, arkansas, and travels north at 90 kilometers per hour. another train leaves at the same time and travels south at 80 kilometers per hour. how long will it take before they are 680 kilometers? apart?

The height of a plant, in inches, p years after planting it is given by the polynomial function r(p) = -2p% + 270p. find the height of the plant when p = 90 years.

Alexandra drove from michigan to colorado to visit her friend. the speed limit on the highway is 70 miles per hour. if alexandra's combined driving time for the trip was 14 hours how many miles did alejandra drive?