Nominal NPV and real NPV

The answer does not show two approaches to calculating the nominal NPV. The first part of the answer calculates the nominal/actual cash flows and discounts at the nominal/actual cost of capital. (And after are the workings for getting the nominal cash flows). The second part of the answer calculates the real cash flows, by taking the nominal flows and removing the general rate of inflation of 3.7%. It then discounts the real cash flows at the real cost of capital of 8%.

Yes.

how is it calculated,,like a question which has sales, selling price, variable cost, fixed costs and inflation. can u explain in detail involving an example will be much appreciated

It is calculated exactly as I explained in my previous reply. Have you watched my lectures on investment appraisal with inflation?