Electric Charge Is Distributed Over the Unit Disk $x ^ { 2 } + y ^ { 2 } \leq 1$

Short Answer

Electric charge is distributed over the unit disk $x ^ { 2 } + y ^ { 2 } \leq 1$ so that the charge density at (x, y) is $\sigma ( x , y ) = 1 + x ^ { 2 } + y ^ { 2 }$ (measured in coulombs per square meter). Find the total charge on the disk.