Please explain how the PVA(10%) is worked out since that's where I get stuck, also, double check my already posted answers, thank you.

Balloons By Sunset (BBS) is considering the purchase of two new hot air balloons so that it can expand its desert sunset tours. Various information about the proposed investment follows: (Future Value of $1. Present Value of $1, Future Value Annuity of $1, Present Value Annuity of $1.) (Use appropriate factor(s) from the tables provided.) Initial investment (for two hot air balloons) Useful life Salvage value Annual net income generated BBS's cost of capital $ 522,000 10 years $ 52,000 46,458 7% Assume straight line depreciation method is used. Required: Help BBS evaluate this project by calculating each of the following: 1. Accounting rate of return. (Round your answer to 2 decimal places.) 2. Payback period. (Round your answer to 2 decimal places.) 3. Net present value (NPV). (Do not round intermediate calculations. Negative amount should be indicated by a minus sign. Round the final answer to nearest whole dollar.) 4. Recalculate the NPV assuming BBS's cost of capital is 10 percent. (Do not round intermediate calculations. Negative amount should be indicated by a minus sign. Round the final answer to nearest whole dollar.) 8.90 % 5.59 years 1. Accounting rate of return 2. Payback period 3. Net present value 4. Net present value assuming 10% cost of capital