依据药物的化学结构判断，强心作用最强的药物是
A: [img=513x155]1803b4a9a40c2a8.gif[/img]
B: [img=368x148]1803b4a9b723824.bmp[/img]
C: [img=284x138]1803b4a9cb0f904.bmp[/img]
D: [img=431x142]1803b4a9d4af015.jpg[/img]
A: [img=513x155]1803b4a9a40c2a8.gif[/img]
B: [img=368x148]1803b4a9b723824.bmp[/img]
C: [img=284x138]1803b4a9cb0f904.bmp[/img]
D: [img=431x142]1803b4a9d4af015.jpg[/img]
举一反三
- For what values of a and b will [img=746x216]1803474d8173a86.png[/img]be differentiable for all values of x? A: a=3/4, b=9/4 B: a=3/2, b=9/2 C: a=3/4, b=9/2 D: a=3/2, b=9/4
- 设随机变量X[img=138x21]17e438ba4537f6f.jpg[/img],则由切比雪夫不等式[img=134x19]17e43eeb4a5ffad.jpg[/img] A: 1/9 B: 4/9 C: 8/9 D: 1
- 设随机变量X[img=138x21]17e0bcf1c82597b.jpg[/img],则由切比雪夫不等式[img=134x19]17e0bd06202ebd9.jpg[/img] A: 1/9 B: 4/9 C: 8/9 D: 1
- 设随机变量X,Y有D(X)=4, D(Y)=9,[img=91x21]17e447e132da9ab.png[/img],则ρXY = ____
- 设随机变量X服从b(2,p)分布,随机变量Y服从b(3,p)分布。若[img=90x41]17e441ea7c518a0.png[/img] 则[img=63x26]17e441ea85da5ea.png[/img]= A: 8/27 B: 4/9 C: 19/27 D: 5/9