$3\mathrm{.}1.$ Find arbitrage opportunities for USD$/$GBP

Market A: $,$ EURUSD $=\frac{1\mathrm{.}1358}{1\mathrm{.}1360}$

EUR$/$GBP $=\frac{0\mathrm{.}7357}{0\mathrm{.}7362}$

Market B: $,$ USD$/$EUR $=\frac{0\mathrm{.}7915}{0}\frac{?}{7916}$

$US\frac{D}{G}BP=\frac{0\mathrm{.}6433}{0\mathrm{.}6439}$

$3\mathrm{.}2.$ You are a Vietnamese exporter with a payment of USD $480,000$ in $6$ months. You signed an option contract with the VND $23,407/$USD exercise price. The current spot price is $22,765$ VND$/$USD$.$ The premium $($option fee$)$ is VND $615/$USD$.$ How would you decide if the spot exchange rate is $24,012$ VND$/$USD after $6$ months? How much would you have to pay?