Provide an Appropriate Response $y$ -Axis to Generate a Solid $y = x$

Essay

Provide an appropriate response.
-The region shown here is to be revolved about the $y$ -axis to generate a solid. Which of the methods (disk, washer, shell) could you use to find the volume of the solid? How many integrals would be required in each case?


$y = x$
$y = 4 x - x ^ { 2 }$