An intramuscular injection is a technique delivering a medication that is deep into the muscles. If intramuscular is administered too high then the efficacy of the vaccine might be reduced as it is not injected in the right site. It might also cause to injure blood vessels so it should be injected in the correct site and depth.
To view space and the foreign objects scientist may find. Also for learning purposes because it financially cost a lot to send scientists to space for research. So for research purposes.
Fat cells are specialised for storage
Yes, a plant would as long as a living creature is in the area to exchange oxygen and carbon dioxide. It is not totally necessary for other plants to be in the immediate vicinity but is necessary for all living things to live. As mentioned before carbon dioxide and oxygen must be exchanged. (The more the merrier(do not add this)).<span />