The image contains three questions. The first question asks about the principle of DRY (Don't Repeat Yourself). The second question asks about the number of operands the '!' operator uses. The third question asks about whether $8\% -4 == 8\%4$.

1. Problem Description

The image contains three questions.

The first question asks about the principle of DRY (Don't Repeat Yourself).

The second question asks about the number of operands the '!' operator uses.

The third question asks about whether $8\% -4 == 8\%4$.

2. Solution Steps

First question: What is the principle of DRY (Don't Repeat Yourself)?

The DRY principle states that "Every piece of knowledge must have a single, unambiguous, authoritative representation within a system." This means avoiding duplicating code to improve maintainability and reduce errors.

Second question: How many operands does the '!' operate on?

The '!' operator is the logical NOT operator. It is a unary operator, which means it operates on only one operand.

Third question: $8\% -4 == 8\%4$?

In most programming languages, the modulus operator (%) returns the remainder of a division.

$8\% -4$ calculates the remainder of 8 divided by -

4. $8 \div -4 = -2$ with a remainder of $0$. So $8\% -4 = 0$

$8\% 4$ calculates the remainder of 8 divided by

4. $8 \div 4 = 2$ with a remainder of $0$. So $8\%4 = 0$

Therefore, $8\% -4 == 8\%4$ is true.

3. Final Answer

First question: Avoid duplicating code to improve maintainability and reduce errors.

Second question: 1

Third question: True