The control group outs the one that you don't change. The reason you don't change it is because you use it as a comparison with the other groups.
Answer:
resultant force, force, acceleration, physics, and rotation
Answer:
These spheres are closely connected. For example, many birds (biosphere) fly through the air (atmosphere), while water (hydrosphere) often flows through the soil (lithosphere). Interactions also occur among the spheres; for example, a change in the atmosphere can cause a change in the hydrosphere, and vice versa.
Explanation:
Hope this helps you!:)
The basics would be that you'd need to find out if they could exchange genetic information. If not, they couldn't be considered part of one species. Set-up 2 artificial environments so both groups would produce pollen at the same time. Fertilise both plants with the other's pollen. Then fertilise the plants with pollen from their own group.
Count the number of offspring each plant produces.
If the plants which were fertilised by the opposite group produce offspring, they are of the same species. You can then take this further if they are of the same species by analysing if there is any difference between the number (and health) of offspring produced by the crossed progeny and by the pure progeny. You'd have to take into account that some of them would want to grow at different times, so a study of the progeny from their first sprout until death (whilst emulating the seasons in your ideal controlled environment). Their success could then be compared to that of the pure-bred individuals.
Make sure to repeat this a few times, or have a number of plants to make sure your results are accurate.
Or if you couldn't do the controlled environment thing, just keep some pollen one year and use it to fertilise the other group.
I'd also put a hypothesis in there somewhere too.
The independent variable would be the number of plants pollinated. The dependant variable would be the number of progeny (offspring) produced.