Mary paid $$456$ for an annual contract to an ISP on July $1,2012.$ She terminated her contract with the ISP on March $8.$ The contract requires to refund a prorated amount to the exact number of days remaining in the period of coverage. A $$50$ service charge is then deducted. What refund will Mary receive? A$.$$$54\mathrm{.}94$B$.$$$0$C$.$$$50$D$.$$$92\mathrm{.}42$E$.$$$142\mathrm{.}42$