Alevel 0.90 confidence interval is a) any interval with margin of error â± 0.90. b) an interval computed from sample data by a method that has probability 0.90 of producing an interval containing the true value of the parameter of interest. c) an interval with margin of error â± 0.90, which is also correct 90% of the time. d) an interval computed from sample data by a method that guarantees that the probability the interval computed contains the parameter of interest is 0.90.

Option B is correct.

Step-by-step explanation:

Confidence interval is the range of the values that the particular probability whose value will lie in the interval.

So, if a level is 0.90 confidence interval it means the value of the probability will lie in the given level.

Therefore, Option B is correct that is an interval computed from sample data by a method that has probability 0.90 of producing an interval containing the true value of parameter of interest.

a28=58

step-by-step explanation:

a1=a1+(n-1)d

a28= 4+ (28-1)2

a28=4+(27)(2)

a28=4+54

a28=58