$7.$An asset was bought for OMR$\mathrm{.}12,000.$ Its accumulated depreciation is OMR$\mathrm{.}7,700$ and the rate of depreciation is $20\%.$ What is the amount of depreciation charge for the current accounting period using reducing balance method?A$)$ OMR$\mathrm{.}1540$B$)$ OMR$\mathrm{.}940$C$)$ OMR. $2400$D$)$ OMR$\mathrm{.}860$