To address the problem, we'll follow the two parts (A and B) as directed.
Part A: Solve the equation \( s = ph + 2b \) for \( p \)
We start with the given equation:
\[ s = ph + 2b \]
To isolate \( p \), we first subtract \( 2b \) from both sides:
\[ s - 2b = ph \]
Next, we divide both sides by \( h \) to solve for \( p \):
\[ p = \frac{s - 2b}{h} \]
So the formula for the perimeter \( p \) of the base is:
\[ \boxed{p = \frac{s - 2b}{h}} \]
Part B: Calculate the perimeter of the base of a rectangular prism
Given that:
- Height \( h = 4 \) meters
- Surface area \( s = 96 \) square meters
- Base area \( b = 8 \) square meters
We will use the formula derived in part A:
\[ p = \frac{s - 2b}{h} \]
Substituting the provided values into the equation:
- Calculate \( 2b \):
\[ 2b = 2 \times 8 = 16 \]
- Substitute \( s = 96 \), \( 2b = 16 \), and \( h = 4 \) into the formula:
\[ p = \frac{96 - 16}{4} \]
- Calculate \( 96 - 16 \):
\[ 96 - 16 = 80 \]
- Divide by \( h \):
\[ p = \frac{80}{4} = 20 \]
Therefore, the perimeter of the base of the prism is:
\[ \boxed{20} \text{ meters} \]