How many minor planets are known to exist in the solar system, using today's classification system?
a. 1
b. 3
c. 2
d. 4
Question 2
What is the frequency, in hertz, of a sound wave (v = 340 m/s) with a wavelength of 68 m?
a. 5 Hz
b. 23120 Hz
c. 340 Hz
d. 0.2 Hz