can you thoroughly explain how to solve this question using formulas not excel

Problem $1$

A company is considering replacing an old machine with a new one. The old machine is

completely depreciated and can be sold for $$50,000$ in the market. The company intends to sell

this machine if it is replaced.

The new machine costs $$450,000.$ The replacement of the machine will require an increase in the

inventories by $$250,000.$

The new machine is going to be depreciated over $4$ years to $0$ salvage value.

The new machine will increase annual revenue by $$170,000$ in addition it will reduce annual

operating costs by $$30,000.$

This new machine can be sold for $$100,000$ in $4$ years.

The project$$s life is $4$ years. The company$$s tax rate is $30\%$ and the cost of capital is $12\%.$

A$)$ What is the CF$0?$

B$)$ What is CF$4($the cash flow to be used in NPV calculations$)?$

C$)$ What is the NPV of the project?