Answer:
Since many viruses can infect a large number of different cell types, ... An example is potato yellow dwarf virus, which can grow in leafhoppers
C=2πr and x^2+y^2=r^2
r=4 because of the equation (16)^1/2 is 4
C=8π
Answer: 
Each term is half of the previous one, so the common ratio is 1/2. Then to get from the first term to the nth term, you have to take n - 1 steps, multiplying by 1/2 each time and by 6000 to account for the first term.
i hope this helps! :D
Answer:
5
Step-by-step explanation:
took the test