The function of the water balloon is an illustration of a quadratic function.
The balloon will splat on the ground after 2.5 seconds
The function is given as:

When the balloon splats on the ground, the value of h(t) is 0.
So, we have:

Expand the expression

Factorize the above expression

Factor out 2t - 5 in the 2t - 5

Split the equation into 2

Rewrite as:

Solve for t

The value of t cannot be less than 0 i.e. negative.
So, we have

Divide 5 by 2

Hence, the balloon will splat on the ground after 2.5 seconds
Read more about quadratic functions at:
brainly.com/question/11631534
I assume it is the last one, 3n^2, because the degree is the exponent, which is two and the three is the coefficient, which is next to the variable, plus it is a monomial, so there is only one term, eliminating the first two, the third one is just reversed. Therefore, the answer should be the last one. Hope this helps. :)
x and y are the packs of organic and inorganic fertilizer, respectively.
pounds of nitrogen added = 2x + 6y = 120
pounds of potassium added = 3x + 2y = 54
eliminate the y terms. subtract the first equation from 3 times the second equation.
9x + 6y = 162
-2x - 6y = -120
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7x = 42
x = 6
y = 18