A.I=28.8∠30°A
B.I=20∠30°A
C.I=28.8∠120°A
D.I=28.8∠0°A
A.I=20∠30°A
B.I=28.8∠0°A
C.I=28.8∠30°A
D.I=28.8∠120°A
A.I=28.8∠30°A
B.I=20∠30°A
C.I=28.8∠120°A
D.I=288∠0°A
A.30
B.33.4
C.22.6
D.18.1
A.s=120-30t(0≤t≤4)
B.s=120-30t(t>0)
C.s=30t(0≤t≤4)
D.s=30t(t<4)
求t分布的上侧α分位点:t0.05(8), t0.01(41),t0.10(15),t0.95(30),t0.05(120).