Question

Which sentence contains a supporting detail that answers the question when? In 1867, the United States bought Alaska from Russia for about $7 million. Many Americans thought it was a foolish purchase. They thought Alaska was a wasteland of ice and snow. However, Alaska is rich in oil, fish, and lumber. The purchase of Alaska was a true bargain.

Answer 1

I think the answer is "In 1867, the United States bought Alaska from Russia for $7 million". When you ask the question "when" the question is asking about time.  In this excerpt, when is answered by "in 1987". while the sentence supported it is the event that happened during that time, which is " The US bought Alaska from Russia for $7 million.