Required

$($a$)$ Estimate operating income for a month in which $200$ desks are manufactured and $220$ are sold if the company uses variable

costing.

$($b$)$ Estimate operating income for a month in which $200$ desks are manufactured and $220$ are sold if the entity uses absorption

costing and allocates fixed manufacturing costs to inventory using a rate based on normal capacity of $150$ desks per month.

Please workout and explain