What is the symbol for the micro prefix?

• A. nano- n
• B. micro- µ
• C. milli- m
• D. femto- f

Answer: (B)

Micro indicates one millionth of a unit (10^-6), and its official symbol is the Greek letter mu written as µ. You’ll see it in measurements like µm for micrometers and µs for microseconds. If you don’t have the actual µ available, you might see a plain 'u' used, but the standard symbol is µ. The other prefixes correspond to different scales: nano is n (10^-9), milli is m (10^-3), and femto is f (10^-15).