Find the volume of the wedge-shaped region (figure 1) contained in the cylinder x2+y2=81 and bounded above by the plane z=x and below by the xy-plane.

Pepe and leo deposits money into their savings account at the end of the month the table shows the account balances. if there pattern of savings continue and neither earns interest nor withdraw any of the money , how will the balance compare after a very long time ?