DSE 2021 Question 10: Sets, relations and functions

There are four statements. Which of these are true? Statement 1: $\{y \text{ is a rational number} \mid -200 \leq y \leq 200\}$ is a countable set. Statement 2: $\left\{y = \tfrac{m}{n} \mid m \text{ and } n \text{ are integers}\right\}$ is an uncountable set. Statement 3: $\{y \text{ is a real number} \mid 0 \leq y < 0.7\}$ is an uncountable set. Statement 4: $\left\{y = \tfrac{\sqrt{2}}{n} \mid n \text{ is a positive integer}\right\}$ is an uncountable set.