[Physicist]

The simplest way is to look up the sine of a 60 degree angle. If you're not equipped for that, there's another way.

Even $5 calculators have "SIN" buttons nowadays. But I'd give him the points: usually when a student pokes the "SIN" button, the answer he writes down is 0.8666666.

[PatrickHenry]

Even $5 calculators have "SIN" buttons nowadays.

You wippersnappers have it too darned easy! Buncha button pushers! Snort, grumble, harumph ...