Answer:
12
Explanation:
Suppose the four different strains are P, Q, R, S. Thus, the first infection can be from any of the four strains and it occurs in 4 ways.
Since an individual cannot be infected again with the strain from which he/she is been previously infected;
Then, at the second time;
The possible number of strain to be infected with = 4-1 = 3 ways
Thus; the number of possible different levels of severity can be viewed by forming two lettered word P, Q, R, and S without repetition which is:
= 4 × 3
= 12
Answer:
1440
Explanation:
Members except president, secretary and joint secretary = 9−3=6
Their arrangement = 6!
No. of arrangements of secretary and joint secretary at wto places
=2!=2
Total arrangement =2×6!
2 x 6! = 1440
A mutation can allow a organism to adapt to the environment and example can be the case of the peppered moth which has two variations a white colored one and a black colored one. The white colored ones were able to survive better that the darker ones because of how they were able to camouflage with the lichen located in the trees. However, after a while smoke particles that were released by industries darkened the trunk of the trees making the white moths visible and allowing the darker colored ones to survive. Another example can be on how organism can be resistant to bacteria this allows the animal to survive and reproduce offspring with the same mutation. I hope this helps...
<span>A mass of rock formed when a large body of magma cools inside the crust is called a. D. Batholith</span>
