I don't understand how to figure this problem. Can you please help me?

In August, 2017 Jimbo Corporation (a calendar year corporation) purchased used computer equipment for $865,000, the only assets Jimbo purchased this year. Jimbo Corporation used a 21% tax rate and a discount rate of 6% for evaluation.

A.) Assuming Jimbo elected to expense $510,000 under Section 179, what was the after-tax cost of the computers?

B.) If Jimbo purchased the computer equipment in 2019 and elected to expense the entire $865,000 under Section 179, what is the after-tax cost of the computers?