Question $9$: Can you explain step by step please?

Assume a cross$-$rate trader at Soci$$t$$ G$$n$$rale notices that BNP is buying dollars at $Sb(lo\frac{n}{\text{\$}})=0\mathrm{.}6527$ the same as Soci$$t$$ G$$n$$rale$\text{'}$s bid price.

Similarly, he observes that MUFG Bank is buying Japanese yen at $Sb(\frac{\text{\$}}{}$#$)=1\mathrm{.}4300,$ also the same as Soci$$t$$ G$$n$$rale$.$

He next finds that a Cr$$dit Agricole is making a direct market between the euro and the yen, with a current ask price of $Sa(lo\frac{n}{})=1\mathrm{.}1604.$

Prove that there is an arbitrage opportunity.