A.低阶无穷小
B.高阶无穷小
C.同阶但不等价无穷小
D.等价无穷小
[单选题]A.低阶无穷小B.高阶无穷小C.同阶但不等价无穷小D.等价无穷小
[单选题]A.低阶无穷小B.高阶无穷小C.同阶但不等价无穷小D.等价无穷小
[单选题]A.低阶无穷小B.高阶无穷小C.同阶但不等价无穷小D.等价无穷小
[单选题]A.2∶3∶6B.3∶2∶1C.D.1∶4∶9
[单选题]A.2∶3∶6B.3∶2∶1C.D.1∶4∶9
[单选题]A.33°41′24.24″B.56°31′39″C.56°18′35.76″D.34°09′06″
[单选题]A.33°41′24.24″B.56°31′39″C.56°18′35.76″D.34°09′06″
[单选题]A.B.C.D.条件不明确,正负压及相应的自然通风量无法确定