Consider a one$-$period call option on the British pound. Suppose that the current exchangerate is USD$/$GBP $2,$ the exercise price is USD$/$GBP $1\mathrm{.}9,$ the one$-$period risk$-$free rate on the USDis $5\%,$ and the one$-$period risk$-$free rate on the GBP is $10\%.$ Suppose that the spot rate caneither go up by a factor of $1\mathrm{.}1($to USD$/$GBP $2\mathrm{.}2)$ or down by $0\mathrm{.}9($to USD$/$GBP $1\mathrm{.}8).($a$)$ Write down the two equations that show how one can replicate the cash flow fromthe option by investing in the foreign currency and borrowing domestically. What is the valueof the call option, using the replication approach?$($b$)$ Compute the risk$-$neutral probabilities and use these to value the above call option.