How much is a Mbtc?
mBTC=millibitcoin=1 thousandth of a bitcoin=0.001BTC=0.00552 USD.
uBTC=microbitcoin=1 millionth of a bitcoin=0.000001BTC=0.0000000552 USD.
with a little asterisk on that. "0.00552 USD, at the current BTC/USD exchange rate of $5.52."