题目详情
单选题 Listen to the news reports and choose the best answer to each question you hear小题:News item 1
A. When there are more than 600 micrograms of dust per square meter of land.
B. When there are more than 800 micrograms of dust per square meter of land.
C. When there are more than 600 micrograms of dust per cubic meter of air.
D. When there are more than 800 micrograms of dust per cubic meter of air.

学科:默认课程
时间:2025-12-11 13:58:31
相关题目
相关作业
