i$.$ Show $($with clear workings$)$ how the present value of $100$ received ten years from now differs depending on whether the discount rate is $10\%$ or $50\%.$

ii$.$ Show with clear workings that the NPV of the following project is positive using a discount rate of $25\%.$ The project initial cost $=100$ in year $0$ and there are net positive cash flows of $50$ in year $1$ and $1000$ in year $5.$

iii. Explain the steps in the internal return method of capital appraisal

iv$.$ Show with clear working that the IRR for the following project gives a signal to invest if the company$$s discount rate is $20\%.$

Cost$$ in year $0=400,000.$ Net revenue in year $1=200,000$ and in year $2=400,000$