What is a rational number between -1/4 and 2/5

The area of a rectangle is 54x^9y^8 square yards. if the length of the rectangle is 6x^3y^4 yards, which expression represents the width of the rectangle in yards

Tom wants to order tickets online so that he and three of his friends can go to a water park the cost of the tickets is 16.00 per person there is also a 2.50 one-time service fee for ordering tickets online write an expression in term of n that represents the cost for n ordering tickets online

Use the method of cylindrical shells to find the volume v generated by rotating the region bounded by the curves about the given axis. y = 7ex, y = 7e^-x, x = 1; about the y-axis