$6.$ A U$.$S$.$ speculator enters a futures contract for June delivery of SFr$125,000$ on January$26.$ The futures exchange rate is $$0\mathrm{.}65/$SFr$.$ He believes that the spot rate for Swiss$$ franc at the maturity date will be $$0\mathrm{.}70/$SFr$.$ The margin requirement is $2\%.$

a$.)$ If his expectations are correct, what would be his rate of return on the$$ investment?$$ b$.)$ If the spot rate for Swiss franc on the maturity date is $5\%$ lower than the futures$$ exchange rate, how much would he lose on the futures speculation?$$

c$.)$ If there is a $70\%$ chance that the spot rate for Swiss franc will increase to $$0\mathrm{.}70$ at$$the maturity date, would you speculate in the futures market?$$