A 5 B 13 C 7 D -5 已知 $D (X) =4$, $D(Y)=9$, $\rho_{XY}=0.5$, 则 $D(X-Y)=
[单选题]患者,女性,初潮13岁,周期24~28d,经期4~5d,应简写为A.13(4~5)/(24~28)天B.13(24~28)/(4~5)天C.13/(4~5)(24~28)天D.13/(24~28)(4~5)天E.(24~28)/(4~5)13天
[主观题]比较。5/13和8/135/7和5/114/5和7/82/9和1/6
[单选题]:-5,-1,5,13,22,( )。A.29B.40C.32D.35
[单选题]2, 5, 13, 38, ( )A.121 B. 116 C. 106 D. 91
[单选题]动物类药水分含量应是A.3%~5%B.5%~10%C.5%~8%D.7%~13%E.8%~20%
N(-1,1) C.N(0,13) D. N(-1,13)
[单选题]2, 5, 13, 38, ( )A.121B.116C.106D.91
[单选题]5,13,37,109,( )A.136 B231 C.325 D.408
[单选题]1, 2, 5, 13, 34, ( )。A.69B.75C.89D.95