Present value of the depreciation tax shield

Question

Problem:

New asset                        $400,000
salvage value                      30,000
old equpiment tax-basis        60,000
revenues                            200,000
savings first three years @   120,000
fourth year                           90,000
tax rate                                  40%
after-tax cost                          10%

Q1. What is the present value of the depreciation tax shield for the new asset for Year 1?

Q2. What are the cash flows (net of tax) associated with the disposal of the old asset?

Q3. What is the investment 's net present value (after tax)?