Let's address each question one at a time:

1. The area of a rotunda is 21.98 square feet. What is the length of its diameter?

Formula:
The area of a circle is $A = \pi r^2$, where $r$ is the radius and $\pi = 3.14$. The diameter $d = 2r$.

Solution:

1. Given $A = 21.98$, solve for $r$: $r^2 = \frac{A}{\pi} = \frac{21.98}{3.14} \approx 7$ $r = \sqrt{7} \approx 2.65 \, \text{feet}.$

2. Find the diameter: $d = 2r = 2 \times 2.65 \approx 5.3 \, \text{feet}.$

Answer: The diameter is approximately 5.3 feet.

2. Find the volume of a Rubik's cube if one of its sides measures $(x + 4)$ millimeters.

Formula:
The volume of a cube is $V = s^3$, where $s$ is the side length.

Solution:
If the side length is $(x + 4)$, then: $V = (x + 4)^3.$

Answer: The volume is $(x + 4)^3 \, \text{mm}^3$.

3. Write the polynomial function $P(x)$, with the zeros 2 of multiplicity three and $-1$.

Hint: Write the zeros as factors.

Solution:

1. The zero $2$ of multiplicity 3 corresponds to the factor $(x - 2)^3$.
2. The zero $-1$ corresponds to the factor $(x + 1)$.

The polynomial is: $P(x) = (x - 2)^3 (x + 1).$

Answer: The polynomial is $P(x) = (x - 2)^3 (x + 1)$.

4. A farmer has a poultry farm whose area is expressed by the polynomial function $f(x) = 8x^2 + 97x + 12$ square meters. What is the actual land area of the poultry farm if $x = 3$?

Hint: Evaluate the function at $x = 3$.

Solution:
Substitute $x = 3$ into $f(x)$: $f(3) = 8(3)^2 + 97(3) + 12$ $f(3) = 8(9) + 291 + 12$ $f(3) = 72 + 291 + 12 = 375.$

Answer: The actual land area is 375 square meters.

Let me know if you want a detailed breakdown of any question or if you have further questions. Here are some related questions to explore further:

1. What would the diameter of a circle be if its area were doubled?
2. How does the volume of a cube change if its side length doubles?
3. How can we factorize a polynomial given only one zero?
4. What is the practical significance of a zero's multiplicity in a polynomial?
5. How would the function $f(x)$ behave as $x \to \infty$?

Tip: Always double-check your calculations, especially when using approximations for constants like $\pi$.