A Maths teacher taught rational numbers and the properties of rational numbers to the students. After the explanation, she gave some questions to students to check their knowledge.
Based on this situation try to find the answers for the below questions.
1. The teacher writes the following on the board the equation \(\frac{2}{3}+\frac{5}{4}=\frac{5}{4}+\frac{2}{3}\) represents
2. The teacher writes the second question the equation \((\frac{5}{3}+1)+\frac{2}{5}=\frac{5}{3}+(1+\frac{2}{5})\) represents
3. Which of the following operations is commutative for rational numbers
4. The expression \((a+b)+y=a+(b+y)\) is an example of