Which represents a quadratic function ?

Step-by-step explanation:

Quadratic function-

It is a function that can be represented by an equation of the form , where

In a quadratic function, the greatest power of the variable is 2.

As in the first option the highest power is 3, so it is not a quadratic function.

Even though the power of x is 2 in the third option, but as it is in the denominator, so the overall power of x becomes -2. Hence it is not a quadratic function.

As the coefficient of is 0 in case of fourth option, so it is not a quadratic function.

Equation in option 2 satisfies all the conditions of quadratic function, hence it is the quadratic function.

on friday there were 15 birds

the answer is simply just 6n add the two together as they have an n