4. light travels at 3.0 % 10% m/s. how
* many seconds go by from the moment
the starter's pistol is shot until the smoke
is seen by the track timer 100 m away?

What would the difference of spectral lines emitted by hydrogen gas in distant galaxies which is normally found at a wavelength of 21 cm on earth, be observed at 21.1 centimeters?

Which best represents the law of conservation of mass ?

One number is said to be an "order of magnitude" larger than another number if choose one: a. it is 10 times larger. b. it is 5 times larger. c. it is 3 times larger. d. it is 100 times larger. e. it is 2 times larger.