are you for real? Get out your calculator. We know that 1000 milliamps = 1 Amp. So therefor 20 milliamps is 2 hundreths of 1 amp. or 0.020A. Do you not remember decimal place values, tenths, hundredths, thousandths, ten thousandths etc....
let's try this another way, you have 2 pennies, what is...