Answer:
The correct options are 1, 3 and 4.
Step-by-step explanation:
We need to find the expressions whose simplified form is a rational number.
Rational number: If a number is defined in the form of p/q where p and q are integers and q≠0, then it is called a rational number.
For example: 0,2, 4.3 etc.
Irrational number: If a number can not defined in the form of p/q, where p and q are integers and q≠0, then it is called an irrational number.
First expression is

12 is a rational number.
Second expression is

is an irrational number.
Third expression is

21 is a rational number.
Fourth expression is

5 is a rational number.
Therefore, the correct options are 1, 3 and 4.
Answer:
I suggest you use Socratic, it solves questions like this.
Step-by-step explanation:
Answer:
Only option C shows a function
Step-by-step explanation:
The vertical line test is a visual way to determine if a curve is a graph of a function or not. A function can only have one output, y, for each unique input, x. This means that a vertical line made in the domain of the function can crosses the curve of the function only once. If it crosses the curve of the function more than once, then the curve is not a function.
In option A, a vertical line would cross two values, so it is not a function.
The curve of option B is a vertical line itself, so a vertical line would intersect an infinite amount of points; then it is not a function.
Option C is a function because a vertical line would only intersect the function's curve (which is a line) once.
A triangular prism<span> has 5 faces, 3 being rectangular and 2 being </span>triangular<span>. The </span>area<span> of the rectangular faces can be found by multiply the base and height lengths together. The </span>area<span> of the </span>triangular<span> faces can be found by multiplying the base and height and dividing by 2.</span>