Answer: A <em>plane </em>
This needs to be 20 characters long so this is ok
Step-by-step explanation:
The line above the letter means "complement". If X is a set, the the complement of X (denoted by X with a line above it) is the set of all things not in X...If X is a set, then the complement of X (denoted by X with a line above it) is the set of all things not in X.
Sorry if it was complicated
Answer:
He must survey 123 adults.
Step-by-step explanation:
In a sample with a number n of people surveyed with a probability of a success of
, and a confidence level of
, we have the following confidence interval of proportions.
In which
z is the z-score that has a p-value of
.
The margin of error is:

Assume that a recent survey suggests that about 87% of adults have heard of the brand.
This means that 
90% confidence level
So
, z is the value of Z that has a p-value of
, so
.
How many adults must he survey in order to be 90% confident that his estimate is within five percentage points of the true population percentage?
This is n for which M = 0.05. So






Rounding up:
He must survey 123 adults.