The following table is the balance sheet of the Bank of Ghana. Ghana International Bank's reserve ratio is 10%.

assets	liabilities
reserves $ 20million T-bond $ 50million mortgages $130million	checkable deposits $150million bank capital $ 50million

I) If Ghana International Bank's net income (net income) is $10 million, interest income is $30 million, and interest expense is $15 million, how much is Ghana International Bank's ROA, ROE, and net interest margin (NIM), respectively?

ii) Currently, how much are required deposits and excess deposits at the Bank of Ghana?