A) Knowledge:

- Encircling perfect square numbers helps students develop knowledge about numbers and their properties.
- It allows them to understand the concept of perfect square numbers, which are numbers that can be obtained by multiplying an integer by itself.
- By identifying and encircling perfect square numbers, students gain knowledge about the specific numbers that satisfy this property.
- This knowledge helps students recognize patterns and relationships between numbers, further enhancing their mathematical understanding.

b) Application:

- Encircling perfect square numbers also helps students apply their knowledge of numbers in a practical way.
- By actively searching for and identifying perfect square numbers in a given set of numbers, students are applying their knowledge to real-world scenarios.
- This application of knowledge strengthens their problem-solving skills and helps them see the relevance of mathematics in everyday life.
- It also allows students to practice their mental math skills, as they need to quickly determine if a number is a perfect square or not.

c) Skill:

- Identifying perfect square numbers requires a certain level of skill in mathematics.
- Students need to be able to calculate the square root of a number or recognize the pattern of perfect square numbers.
- By regularly practicing this skill, students become more proficient in quickly determining whether a number is a perfect square or not.
- This skill is transferable to other areas of mathematics, as it helps students develop a deeper understanding of number properties and relationships.
- It also improves their ability to solve problems and think critically.

d) Understanding:

- Encircling perfect square numbers contributes to students' overall understanding of numbers and their properties.
- Through this activity, students gain a deeper understanding of the concept of perfect squares and the relationship between square roots and perfect squares.
- They also develop an appreciation for the patterns and structures that exist within the number system.
- This understanding helps students build a solid foundation in mathematics, which can support their learning in more complex topics in the future.

In conclusion, encircling perfect square numbers in a given set of numbers achieves the objective of knowledge. It allows students to develop their understanding of numbers, apply their knowledge in practical situations, enhance their mathematical skills, and deepen their overall understanding of mathematics.