The answer should be A, if he marked it up 70% just multiply 66 by 1.7 for your answer.
Primary sources contain information
A. with the advantage of hindsight and the perspective of an outside observer and may be more objective.
B. provided by someone who's been through an event. It's a firsthand account that lends a unique perspective.
C. on statistics gathered after an important historical event.
D. on psychological information gathered from raw data from psychological tests.
I'm not sure what the question is here. If an answer is communicative property, go with that. If it is asking for
, the answer is about 84.8230016469.