Assume a bank has estimated that the loss given default (LGD) on mortgage loans to be 30% of the outstanding loan value and the probability of default on such loans derived from internal and external sources is 10%. If the risk-free rate in the country (R) is 4%, and the risk premium (RP) that the bank demands on such loans to cover the risk of default is 2%, what would be the interest rate (r) that the bank should charge on the mortgage loan?