Complete each statement to describe a diagram that represents each situation. Then complete the addition expression to represent the final temperature. a. The temperature was 80° F and then fell 20° F. A number line diagram with an arrow that starts at , is units long, and points to the left. addition sentence: 10 + ( -4 ) b. The temperature was -13° F and then rose 9° F. A number line diagram with an arrow that starts at , is units long, and points to the right. addition sentence: + c. The temperature was -5° F and then fell 8° F. A number line diagram with an arrow that starts at , is units long, and points to the left. addition sentence: + ( )