Answer:
mega-
kilo-
giga-
Explanation:
The standard unit of distance is in meters. Distance is the length of path covered by a body.
Only mega, kilo and giga are units that are larger than the base unit of distance which is meters.
Mega is of the order 10⁶
Kilo is of the order 10³
giga- is of the order 10⁹
The prefixes below are submultiples:
centi- 10⁻²
micro- 10⁻⁶
nano- 10⁻⁹