a) A shop sells a speaker for NOK 8,000 ex. VAT. The VAT on the loudspeaker is 25%. What will the price the customer pay for the loudspeaker? What percentage of this price is VAT?

b) Martin saves money in funds. He has an investment portfolio with a value of NOK 80,000 at the start of the year. Over the next six months, the value of the portfolio falls by 12% and reaches a bottom. Over the next six months, the value of the portfolio rises by 12%. What is the value of the portfolio at the end of the year?

c) Amir has got a sales job in a company that sells PCs and mobile phones to business customers. He has received two salary offers. In the first offer, he has a fixed monthly loan of NOK 38,000. In the second offer, he has a fixed monthly salary of NOK 32,000 in addition to a commission of NOK 400 for each product he sells. How many products must he sell per month in order for the two salary packages to give the same salary ?

Please give me a answer with proper calculation....thank you!