从一批木材中随机抽取100根，测其小头直径，得样本平均值为11.2[tex=1.286x1.286]eZajcdVh/P/OwuKZt1VDQg==[/tex], 已知标准差为2.6[tex=1.286x1.286]eZajcdVh/P/OwuKZt1VDQg==[/tex]，问这批木材的小头直径的平均值是否在12[tex=1.286x1.286]eZajcdVh/P/OwuKZt1VDQg==[/tex]以上？（取[tex=3.643x1.286]uCvVj7oT0SfIUc6Wr9C1dTT15cLAL94/PRfoMl+38ps=[/tex]）

中骨盆横径为[input=type:blank,size:4][/input]之间的距离,平均为[input=type:blank,size:4][/input][tex=1.286x1.286]eZajcdVh/P/OwuKZt1VDQg==[/tex]。

某校男子篮球队10名队员的身高（单位：[tex=1.286x1.286]eZajcdVh/P/OwuKZt1VDQg==[/tex]）如下：179, 182, 170, 174, 188, 172, 180, 195, 185, 182。则这组数据的中位数和众数分别是 A: 181, 181 B: 182, 181 C: 180, 182 D: 181, 182 E: 180, 181

炎热夏天喝饮料解暑，通过吸管啜饮（如图所示，单位：[tex=1.286x1.286]eZajcdVh/P/OwuKZt1VDQg==[/tex]）最初时刻，杯中饮料的竖直高度为[tex=1.786x1.286]HDipPnP96HvFgfBwewTOeQ==[/tex]，若饮料的密度是[tex=3.929x1.286]zN70chPgOIBuEgvzeM6zuA==[/tex]，问饮完这杯饮料需要做多少功？[img=141x178]1776bad1f9d420d.png[/img]

随机地从一批钉子中抽取[tex=1.0x1.286]RJXjcyRcc2LJEMSQSxyRbA==[/tex]枚，测得其长度(单位;[tex=1.286x1.286]eZajcdVh/P/OwuKZt1VDQg==[/tex])为[tex=26.357x1.286]1mq+ocKVPibXy9iYgRyHl9NLipR0m5mhXI79VOZwaaKWy44R3aKQN6LVwliPT8at77/DEq/fxCFFpM5P5Ln3fb/ExZTDcYYtQ/M8h6HVVhM=[/tex][tex=15.143x1.286]1mq+ocKVPibXy9iYgRyHl5QrK02flu3qsi/CcMnsOfhgparhbvvMRTiDctBNocqR[/tex]。设钉长分布为正态分布，试求总体平均数[tex=0.643x1.286]LHHF5r8Y9VBlpolr/GDm2w==[/tex]的置信水平为[tex=1.857x1.143]6ct+iwoR4UNC8as2/Ebayw==[/tex]的置信区间:若[tex=0.571x0.786]G/buLKOLYVDEKMZ76t752w==[/tex] 末知。

for i in range(b.max_row): for j in range(b.max_column): print(b.cell(row=i,column=j).value)上面语句运行的结果是：__________。 A: 1 1 1 1 1 1 1 1 1 1 B: 1111111111 C: 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 D: 出现异常

【单选题】CDMA通信的基站,假定基站A的码片序列是+1 +1 +1 -1 -1 +1 -1 -1,基站发射bit为101时,实际发射的信号是 A. +1 +1 +1 -1 -1 +1 -1 -1 +1 +1 +1 -1 -1 +1 -1 -1 –1 –1 –1 +1 +1 –1 +1 +1 B. +1 +1 +1 -1 -1 +1 -1 -1 –1 –1 –1 +1 +1 –1 +1 +1 +1 +1 +1 -1 -1 +1 -1 -1 C. +1 +1 +1 -1 -1 +1 -1 -1 +1 +1 +1 -1 -1 +1 -1 -1 +1 +1 +1 -1 -1 +1 -1 -1 D. –1 –1 –1 +1 +1 –1 +1 +1 –1 –1 –1 +1 +1 –1 +1 +1 –1 –1 –1 +1 +1 –1 +1 +1

for i in range(1,11): for j in range(1,11): b.cell(row=i,column=j).value=1 #b是一个工作表对象for i in range(1,11): for j in range(1,11): print(b.cell(row=i,column=j).value,end=" ") print()上面程序代码运行的结果是（）。 A: 1 B: 1 1 1 1 1 1 1 1 1 1 C: 1111111111 D: 1 1 1 1 1 1 1 1 1 11 1 1 1 1 1 1 1 1 11 1 1 1 1 1 1 1 1 11 1 1 1 1 1 1 1 1 11 1 1 1 1 1 1 1 1 11 1 1 1 1 1 1 1 1 11 1 1 1 1 1 1 1 1 11 1 1 1 1 1 1 1 1 11 1 1 1 1 1 1 1 1 11 1 1 1 1 1 1 1 1 1

下列哪个码片序列不能用于CDMA通信 A: ( -1 -1 -1 +1 +1 -1 +1 +1 ) B: ( -1 -1 +1 -1 +1 +1 +1 -1 ) C: ( -1 +1 -1 +1 +1 -1 -1 -1 ) D: ( -1 +1 -1 -1 -1 -1 +1 -1 )

请仔细观察下面行列式的计算过程，如果四个等号都理解了，请选择A，否则请选择B。 | a 1 1 1 1 | |a＋4 a＋4 a＋4 a＋4 a＋4| | 1 a 1 1 1 | | 1 a 1 1 1 | | 1 1 a 1 1 |= | 1 1 a 1 1 | | 1 1 1 a 1 | | 1 1 1 a 1 | | 1 1 1 1 a | | 1 1 1 1 a | | 1 1 1 1 1 | | 1 a 1 1 1 | =(a＋4) | 1 1 a 1 1 | | 1 1 1 a 1 | | 1 1 1 1 a | | 1 1 1 1 1 | | 0 a–1 0 0 0 | =(a＋4) | 0 0 a–1 0 0 | | 0 0 0 a–1 0 | | 0 0 0 0 a–1 | =(a＋4)(a–1)^4