Mode can be defined as the number that appear more than other numbers.
The given chart is:
Anxious behaviors per hour
Subject 1 60
Subject 2 45
Subject 3 20
Subject 4 70
Subject 5 45
Based on the above chart we can see 45 in subject 2 and 45 in subject 5 which in turn means that 45 appear more than others numbers as it appear twice.