Viruses need to be inside a living thing (of course the living thing has to have the right temperature which most living things do) . When they're inside a living thing they start injecting the host's cells with its DNA in order to make more copies of itself which allows the virus to spread. So basically viruses need to be inside something living.
A place where 2 geologic units meet is called contact .
Answer: science
Explanation: she was a scientist
Scientific theories are often so powerful because they have been tested several time by different peoples and they have been found to be true. A scientific theory is a well substantiated explanation for a specific phenomenon which has undergone many observations and experiments and has stand the test of time. Thus, scientific theories always have to be reckon with because they have been severally tested.
Mouth or nose. Then goes into your trachea and into your lungs