Help with these problems

Two airplanes start at the same place and travel in opposite directions,one at 395 miles per hour and the other at 422 miles per hour. how many hours will it take for the planes to be 2451 miles apart?

Y+ 2/y is it a polynomial in one variable or not? and if so, why?

Order the equations from least to greatest based on the number of solutions to each equation.-4^x -1 = 3^(-x) – 2 -3x + 6 = 2^x+13^x – 3 = 2x - 2