You are interested in how consistently children in a day care center check in with their teachers during free play. You decide to observe each child for a 10 minute period and record whether or not he or she looked at the teacher during each of the 40 15-second blocks of time. Each child will have a total possible score of 40 if you score each 15 seconds as 1 for "yes, the child looked," and 0 for "no, the child did not look." What method are you using to quantify your observation? a. Duration b. Frequency c. Interval d. Event