I need to find out NPV, payback, discounted payback, IRR, and profitability index from the information below for 1,000 of car A and 1,000 of car B. The information below is pretaining to a purchase of one car of car A and car B. Thanks so much for your help!! Let know if you have any questions.

I) Car A :

a) Annual net income = (Annual revenue - Annual gas expense - Depreciation - Interest on debt) * (1 - tax rate)

Here, Annual revenue = $20,000

Annual gas expense = Total miles per year / miles per litre * gas price = 40,000/ 28 * $2.68 = $3828.57

Depreciation = ( Cost of car - salvage value)/ no. Of years = ($36,970 - 0) / 4 years = $9242.50

Interest on debt = Car loan * Rate of interest = $36,970 * 8% = $2957.60

Tax rate = 21%

Now,

Annual net income = ($20,000 - $3828.57 - $9242.50 - $2957.60) * (1 - 0.21) = ($3971.33 * 0.79) = $3137.35

b) Operating cash flows (annually) = Annual net income + Depreciation = $3137.35 + $9242.50 = $12,379.85

c) Cash flow from assets (annually) = $12,379.85 (same as point b. as there are no other capital spending)

II) Car B:

a) Annual net income = (Annual revenue - Annual gas expenses - Depreciation - Interest on debt) * (1 - tax rate)

Here, Annual revenue = $20,000

Annual gas expense = Total miles / miles per litre * gas price = 40,000 / 24 * $2.68 = $4466.67

Depreciation = ( Cost of car - Salvage) / no. Of years = ($31,330 - 0)/4 years = $7832.50

Interest on debt = Car loan * Rate of interest = $31,330 * 8% = $2506.40

Tax rate = 21%

Now,

Annual net income = ($20,000 - $4466.67 - $7832.50 - $2506.40) * (1 - 0.21) = ($5194.43 * 0.79) = $4103.60

b) Operating cash flows (annually) = Annual net income + Depriciation = $4103.60 +$7832.50 = $11,936.10

c) Cash flow from assetss(annually) = $11936.10 (same as point b. as there are no other capital spending)

Comparison : Annual net income of car B is higher by $966.25 (4103.60 - 3137.35) but at the same time operating cash flow of A is higher by 443.75 (12,379.85 - 11,936.10).

Note : It is assumed that car loan is taken @ 8% for both the options.