[填空题]Excel中，已知A1=”中华人民国共和”，D1中的公式为〖=Right（Left（A1，4），2）〗，则D1中显示的信息为（）。

[填空题]Excel中，已知A1=”中华人民国共和”，D1中的公式为〖=Mid（A1，3，2）〗，则D1中显示的信息为（）。

[单项选择]已知a₁=(1，1，-1)^T，a₂=(1，1，2)^T，满足a₁、a₂、a₃线性相关的向量a₃=（）。
A. (1，1，0)^T
B. (3，=3，5)^T
C. (-1，0，0)^T
D. (0，0，3)^T

[填空题]

已知a₁，a₂，a₃，a₄，a₅是满足条件a₁+a₂+a₃+a₄+a₅=9五个不同的整数，若b是关于x的方程(x-a₁)(x-a₂)(x-a₃)(x-a₄)(x-a₅)=2009的整数根，则b的值为（）．

[填空题]已知正方体ABCD—A₁B₁C₁D₁中，M是DD₁的中点，O是底面正方形ABCD的中心，P为棱A₁B₁上任意一点，则直线OP与直线AM所成角的大小等于（）．

[单项选择]
Right is right. Right Of course. But is left wrong Well, the Romans used to think so. They thought left-handed people were mistakes of nature. Latin, the language of the Romans, had many Words that expressed this view. Some words we use today still have this meaning. The Latin word "dexter" means "right". The English word "dexterous" comes from this word. It means "handy" ( clever with hands). So, right is handy. But the Latin word for left is "sinister". The English word "sinister" comes from this word. Sinister means "evil" (very bad). Is it fair to call right-handed people handy and: left-handed people evil Well, fair or not, many languages have words that express such beliefs. In old English, the word for left means "weak". That isn’t much of an improvement over "evil".
Not very long ago, children were often forced to write with their right hands. Doctors have since found that this can be very harmful. You should use the hand
A. He can only use his right hand.
B. He can only use his left hand.
C. He can use either his left hand or his right hand.
D. He can use both his left hand and his right han

[填空题]已知A=(a₁，a₂，a₃，a₄)，其中a₁，a₂，a₃，a₄为四维列向量，方程组AX=0的通解为K(2，-1，1，4)^T，则a₃可由a₁，a₂，a

[单项选择]在等差数列a_n）中，已知a₁+a₂+a₃+a₄+a₅=20，那么a₃等于（）。
A. 4
B. 5
C. 6
D. 7

[简答题]已知A₀等于1，A₁等于2，其后各项通式为A_N+1=3(A_N-1)A_N-1，问A₅等于多少

[填空题]a_n为等差数列，已知a₁+a₂+a₃=-24，a₁₁+a₁₃+a₁₅=42，则a₁₉=______。

[填空题]已知向量组a₁=(1，2，0，1)^T，a₂=(2，-1，1，-1)^T，a₃=(3，a，1，0)^T，a₄=(1，2，3，a+3)^T，a₅=(4，3，a，1)^T的秩为3．则其极大线性无关组是______．

[单项选择]在等比数列a_n中，已知a₁和a₁₀是方程3x²+2x-6=0的两个根，则a₄·a₇=（）。
A. -2
B. 2
C. -4
D. 4

[单项选择]已知向量组a₁，a₂，a₃，a₄线性相关，则向量组（）。
A. a₁+a₂，a₂+a₃，a₃+a₄，a₄+a₁线性无关
B. a₁+a₂，a₂-a₃，a₃-a₄，a₄-a₁线性无关
C. a₁+a₂，a₂+a₃，a₃+a₄，a₄-a₁线性无关
D. a₁+a₂，a₂+a₃，a₃-a₄，a₄-a₁线性无关

[单项选择]在Excel 2003中，已知A1单元格中的值为21，B1单元格中的值为22，若在A2单元格中输入函数“=IF(A1＞B1,"1","2")”，按回车键后，则A2单元格显示的值为______。
A. 1
B. 2
C. FLASE
D. TRUE

[填空题]在Excel中，已知在(A1：A10)中已输入了数值型数据，要求在AU中得出如下结果：当(A1：A10)中的平均值不小于60时，AU的值为“合格”，否则为“不合格”。则All单元格应使用的公式为( )。