I need help for this problem

Let R denote a rectangular metal plate given by the region [2, 10] X [2, 6] in the xy -p|ane, with x and 3' given in centimeters. Suppose that the density of the plate is given by p(x. y) = x + y grams/c1712. Use Ax = Ay= 2 and an appropriate Riemann sum to estimate the mass of this plate. Find both an upper and lower estimate of the mass by using appropriate corners of each subrectangle and then average your values to give a better estimate of the exact mass of the plate. Show work and include units with your answer. Use the equation editor (click on the pull-down menu next to an electric plug( 51 v ), choose "View All" and then select MathType at the bottom of the menu)