When plotting numbers on a number line, we need to know about negative and positive numbers. So basically, if we start from zero and go infinitely to the right, we are going in the positive direction. If we are going to the left, it's negative. As we go to the left, the larger the base number is (number without the sign negative) the less value it is. Since you are plotting 9,2, and -4, we put 9 one before 10. 2 is 2 little slashes from 0. Lastly, -4 is 4 to the left from 0. Hope this helps!
You can notice that the january 25th was warmer in comparisson with february 2nd. Becasue in january 25th the temperature was 48°F and in february 2nd the temperature was 24°F. And 48 is higher than 24.