PLEASE HELP IT'S URDGENT I DONT UDNERSTAND

Jamie is hiking up a small mountain. he climbs up at a constant rate of 300 feet/hour until he reaches the peak at 1,500 feet. after that, he hikes down at the same rate to the base of the mountain. the equation that models jamie’s elevation, e, after t hours is e = . jamie’s elevation will be 600 feet after hours and after hours.

The perimeter of a rectangle is 42 inches. if the width of the rectangle is 6 inches, what is the length

The bottom of a vase is a square.each side measury y+11 units.the square has a perimeter of 55 units what is the value of y?