Answer: (c)
Step-by-step explanation:
Given

Here, 
To get
, replace
in
by 

Using
and
it can be concluded that the domain of
is all real numbers except 0.
Therefore, its domain is given by

Option (c) is correct.
Answer:
Is not a type of magnet a domain magnet
None? Unless the second option is supposed to be 10^2 or the fourth option is 50 x 2.
Answer:
The probability that the student answers at least seventeen questions correctly is
.
Step-by-step explanation:
Let the random variable <em>X</em> represent the number of correctly answered questions.
It is provided all the questions have five options with only one correct option.
Then the probability of selecting the correct option is,

There are <em>n</em> = 20 question in the exam.
It is also provided that a student taking the examination answers each of the questions with an independent random guess.
Then the random variable can be modeled by the Binomial distribution with parameters <em>n</em> = 20 and <em>p</em> = 0.20.
The probability mass function of <em>X</em> is:

Compute the probability that the student answers at least seventeen questions correctly as follows:


Thus, the probability that the student answers at least seventeen questions correctly is
.