Step 1: Formula for the sum of internal angles.
The sum of the internal angles of any polygon can be calculated using the formula:
\[
\text{Sum of internal angles} = (n - 2) \times 180^\circ,
\]
where \( n \) is the number of sides of the polygon.
Step 2: Apply the formula for a pentagon.
For a pentagon, \( n = 5 \):
\[
\text{Sum of internal angles} = (5 - 2) \times 180^\circ = 3 \times 180^\circ = 540^\circ.
\]
Step 3: Conclusion.
The sum of the internal angles of a regular pentagon is 540 degrees.
In an experiment to examine the role of exopolymetric substances (EPS) on bacterial growth, a wild-type strain (S⁺) and a mutant strain deficient in EPS production (S⁻) were grown in monocultures as well as in co-culture (in equal proportion of S⁺ and S⁻). The CFU (colony forming units) of these cultures measured after 24 hours are shown in the following figure. 
Which one of the following phenomena best describes the interaction between the wild-type strain (S⁺) and mutant strain (S⁻)?
Match the diseases in Group A with their corresponding causative microorganisms in Group B 
Match the metabolic pathways in Group A with corresponding enzymes in Group B 
Which one of the following matches is CORRECT between the microorganisms given in Group A with their requirement of oxygen in Group B? 