. Elementary particles have the ……… size. 21.smallest
22.The earth can be regarded as a ………. . 22.clock
- The age of universe is ……… s. 23.2 x 1018
24…….. is the language of physics. 24.Mathematics
- There are ……. seconds in one year. 25.3.17 x 107
- The size of the universe is ……… time larger than that of an elementary particle. 26.1041
- A 45 mih-1 is equal to …….. fts-1. 27.66
28.A metre stick is …. than the yard stick. 28.longer
- One gram is equal to …. kg. 29.10-3
- Physics is the subject which studies ………. phenomena. 30.natural
