When heated, allyl aryl ethers and allyl vinyl ethers undergo a reaction called a Claisen rearrangement, a concerted reorganizat
ion of bonding electrons similar to the Diels-Alder reaction. The reaction proceeds through a six-membered, cyclic transition state. Draw the structure of the expected product when this compound undergoes a Claisen rearrangement.
The characteristic being calculated here is the mean or the average of the data set. To check: (20.73 + 20.76 + 20.68 + 20.75)/4 [we divide it by 4 because there are 4 numbers] = 82.92 / 4 = 20.73