Usain Bolt, a Jamaican sprinter, holds the Olympic and world records for the 100-m and 200-m dash, which he achieved during the 2008 Summer Olympics in Beijing, China. He finished the 200-m dash in 19.30 seconds.
What was his speed?

Astronomers discover an exoplanet (a planet of a star other than the sun) that has an orbital period of 3.87 earth years in its circular orbit around its sun, which is a star with a measured mass of 3.59 x 1030 kg. find the radius of the exoplanet's orbit.

The coefficient of friction is a number that represents the resistance to sliding between two in contact with one another.

What is the equation for electrical work?