新版70题里面的三道题~我想破脑袋了从guide上也找不出！！HELP~~~~~


[em49][em49][em49]
87. Question 1: The following program is submitted.
data WORK.TEST;
input Name $ Age;
datalines;
John +35
run;
Which values are stored in the output data set?
A. name age John 35
B. name age John (missing value)
C. name age (missing value) (missing value)
D. The DATA step fails execution due to data errors.
Answer: A 我想知道那个加号是干什么的？？
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93. This question will ask you to provide a line of missing code. Given the following data set WORK.SALES:
SalesID SalesJan FebSales MarchAmt
------- -------- -------- --------
W6790 50 400 350
W7693 25 100 125
W1387 . 300 250
The following SAS program is submitted:
data WORK.QTR1;
set WORK.SALES;
array month{3} SalesJan FebSales MarchAmt;
<insert code here>
run;
Which statement should be inserted to produce the following output?
SalesID SalesJan FebSales MarchAmt Qtr1
------- -------- -------- -------- ----
W6790 50 400 350 800
W7693 25 100 125 250
W1387 . 300 250 550
A.Qtr1 = sum(of month{_ALL_});
B.Qtr1 = month{1} + month{2} + month{3};
C.Qtr1 = sum(of month{*});
D.Qtr1 = sum(of month{3});
Answer: C   选项C中的*是嘛意思？选项A不行么？？

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94. Given the following SAS error log
44 data WORK.OUTPUT;
45 set SASHELP.CLASS;
46 BMI=(Weight*703)/Height**2;
47 where bmi ge 20;
ERROR: Variable bmi is not on file SASHELP.CLASS.
48 run;
What change to the program will correct the error?
A.Replace the WHERE statement with an IF statement
B.Change the ** in the BMI formula to a single *
C.Change bmi to BMI in the WHERE statement
D.Add a (Keep=BMI) option to the SET statement
Answer: A  
为什么是A？难道不是C吗？？