4, because you can't have a negative square root.
Answer:
0.648
No, that is not an unusually low number of correct guesses.
Step-by-step explanation:
Suppose you take a 15 question True or False quiz and you guess on every problem. You only get 3 correct. Then
- correct;
- o\incorrect.
The probability of getting 3 or fewer correct guesses is

Using the criteria that a number 3 is unusually low if P(3 or fewer) ≤ 0.05, we can state that 3 is not an unusually low number of correct guesses.
I think the answer would be 4n