The right option is; orbital period
T stands for orbital period.
Orbital period is the time a certain astronomical object such as planets takes to complete one orbit (360° revolution) around another object such as sun or stars. Orbital period is expressed in different units of time, usually in years, days or hours.
One risk for accessing carbon from the ground is that it may cause soil contamination. Soil when exposed to large amount of gases and other organically decaying materials can absorb these into their make-up. Fossil fuels are extracted from the ground through drilling processes. When the drilling is unsuccessful, pockets created within the soil can create areas for contamination. When soil is contaminated by fossil fuels, it can no longer be use for agricultural purposes.
Find a place in your house to put various lights.
A microscope is to see smaller things that you can’t see and it is a really good tool.
