单选题
There are two questions below，
refer to the following graph.
单选题
What was the range in the daily number of shirts sold during March?
【正确答案】
C
【答案解析】
单选题
The average (arithmetic mean)number of shirts sold per day during February was approximately what percent greater than the average number sold during January?
【正确答案】
D
【答案解析】