W What is the frequency of an electromagnetic wave that has a wavelength of
3.7 x 10-11 m in a vacuum? (The speed of light in a vacuum is 3.00 x 108
m/s.)

i don't see a text, but i am gonna assume this *orbit* the curved path, usually elliptical, described by a planet, satellite, spaceship, etc., around a celestial body, as the sun.

"record the time to complete a chemical reaction" would most likely be part of a lab procedure.