Intervals as Subsets of Real Numbers

Q. Which of the following represent the collection of all the real numbers on a number line?

1. $(-\infty ,\infty ]$
2. $(-\infty ,\infty )$
3. $[-\infty ,\infty ]$
4. $[-\infty ,\infty )$

Q. The diagram shown below represents the interval

1. $[-3,2]$
2. $\{-3,2\}$
3. $(-3,2]$

Q. The correct interval representation for the set $A=\{x:-2\le x<4\}$ is given by

1. $(-2,4)$
2. $(-2,4]$
3. $[-2,4)$
4. $[-2,4]$

Q. $7$ is an element of the interval $(3,7]\text{or}7\in (3,7].$

1. False
2. True