A US MNC should receive $1\mathrm{.}25$ million in $6$ months from today. The US MNC thinks to hedge this AR by buying an option. If the exercise price of the available put option is $$0\mathrm{.}85$ with a premium of $$0\mathrm{.}25$ while the exercise price of the available call option is $$0\mathrm{.}9$ with a premium $$0\mathrm{.}28,$ at what ER would the US MNC let the option expire and use the spot rate?