Hey plsss help me

The first, third, and fourth answer choices represent a function.

Step-by-step explanation:

A relation is a relationship between sets of values. The two quantities that are being related to each other are the input (x-variable) and the output (y-variable). But relations in general aren't always a good way to relate between x and y.

Say that I have situation where I want to give x dollars to the cashier so he can change them to y quarters. Here is a "example" of the relation:

Dollars (x) | Quarters (y)            

       0       |          0                      

        1       |          4                      

       2       |          8

       2       |          12

Do you see something wrong here? Yes! We all know that you can't exchange 2 dollars for 12 quarters. You can only exchange 2 dollars for 8 quarters and only 8 quarters. This is a general reason why we don't rely on general relations for real-life situations. One x-variable does not exactly map to one and only one y-variable.

However, a relation that can map one x-variable to one and only one y-variable is known as a function. Let's make the above example an actual function to prove a point:

Dollars (x) | Quarters (y)            

       0       |          0                      

        1       |          4                      

       2       |          8

       3       |          12

Now, the 3 dollars make 12 quarters as it should. This is how a function should look like.

There are two ways to check if a relation is a function. On a relation, table, or a set of ordered pairs, you have to make sure there is no "x-variable" that repeats. All x-values of a relation have to be unique in order to be a function. On a graph, you can also perform the Vertical Line Test. If you draw vertical lines over a relation and if the lines cross only once, then it is a function. If not, it fails the Vertical Line Test.

So to answer you're question, the first, third, and fourth choices are functions because they all have unique x-variables. The second choice is not a function because it fails the Vertical Line Test.

answer

explanation

the area of a circle is calculated using the formula

or

we can use any of the above formulae to calculate the required. preferably, let us use the latter since the diameter is

we substitute the diameter into the formula to get:

this is the exact value for the area of the circle.

the correct answer is a

this is answer of 144 cubic meters