D. All the answered are correct
Inequalities are used to represent unequal expressions.
The solution set to
is: 
The inequality is given as:

From the inequality above, we have the following observation.
- The value of variable x starts from 7/16 (inclusive)
- The value of variable x has no end (i.e. infinity)
Because, 7/16 is inclusive of the values of x, we make use of the open square bracket i.e. [
We treat
, as an exclusive value. So, we make use of the close parenthesis i.e. )
Hence, the solution set is: 
Read more about inequalities at:
brainly.com/question/20382422
The frequency of waves are determined by the amount of waves that pass a specific point in a certain period of time and Radio stations broadcast their signals at different frequencies so that the range of radio frequencies can be used by many stations.
In maximizing profits (or minimizing loss), a single-price monopolist will charge a price that is greater than the marginal cost.
<h3>
Who is a monopolist?</h3>
A monopolist is usually a term used to refer to a business entity that solely controls the market of a certain product or service without any competitor. In the case of a single-price monopolist, if they charge a price that is greater than marginal cost is the most viable option to maximize profit.
You can learn more about a monopolist here brainly.com/question/13113415
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