I believe the correct answer is B. -5
Answer:
The probability of failure of trial 11 is 
Step-by-step explanation:
Generally one the attributes of a binomial experiment is that the probability of success and failure is constant every trial so given from the question that the probability of success is 0.84 for trial 7 , then the probability of failure of trial 7 will be evaluated as

=> 
And from the attribute stated above the probability of failure of trial 11 is 
To answer this question you must use Pythagorean theorem
a and b are the legs (the sides that form a perpendicular/right angle)
c is the hypotenuse (the side opposite the right angle)
In this case...
a = 3
b = unknown
c = √34
^^^Plug these numbers into the theorem
Simplify
9 + b² = 34
solve for b
= 25
Take the square root of both sides to cancel out the square from the b
√b² = √25
b = 5
Hope this helped!
~Just a girl in love with Shawn Mendes
A) "Dear Sir or Madam:"
That requires a comma, not a colon.