McCrink & Wynn (2004) tested whether 9-month-olds can perform simple arithmetical operations (addition and subtraction; 5+5=10 or 10-5=5) using their magnitude-based estimation system. Note that this is the study with relatively large numbers (SO NOT the study using smaller numbers and Micky Mouse dolls). A) How did they test this for addition and subtraction? In other words, what items did the infants look at during the study and how were they presented? B) What were the results of this study? In other words, what did the data look like this does NOT refer to the interpretation, but rather what the pattern was in the data, e.g.. longer/more looks to X than to Y). Make sure to discuss both the results for addition and for subtraction. C) What do these data mean (this DOES refer to the interpretation)? McCrink & Wynn (2004) tested whether 9-month-olds can perform simple arithmetical operations (addition and subtraction; 5+5=10 or 10-5=5) using their magnitude-based estimation system. Note that this is the study with relatively large numbers (SO NOT the study using smaller numbers and Micky Mouse dolls). A) How did they test this for addition and subtraction? In other words, what items did the infants look at during the study and how were they presented? B) What were the results of this study? In other words, what did the data look like this does NOT refer to the interpretation, but rather what the pattern was in the data, e.g.. longer/more looks to X than to Y). Make sure to discuss both the results for addition and for subtraction. C) What do these data mean (this DOES refer to the interpretation)