The purpose of a collection letter is to ( ).
A. persuade a customer to buy a product
B. give a discount to a potential customer
C. ask a customer to pay a past-due bill
第1题:
A.间隔20秒后,buy( )函数被调用一次
B.间隔20分钟后,buy( )函数被调用一次
C.间隔20毫秒后,buy( )函数被调用一次
D.buy( )函数被持续调用20次
第2题:
A.DROP SEQ_CUSTOMER_ID
B.DELETE SEQUENCE SEQ_CUSTOMER_ID
C.DROP SEQUENCE SEQ_CUSTOMER_ID
D.DELETE SEQ_CUSTOMER_ID
第3题:
第4题:
关于下面函数,哪一个是错误描述?defcount_letter_number(string):letter_count=0digit_count=0forchinstring:
if'a'<=ch<='z'or'A'<=ch<='Z':letter_count+=1elif'0'<=ch<='9':digit_count+=1
returnletter_count,digit_count
A.函数能统计字符串中英文字母出现的次数
B.letter_count+=1可以写做letter_count=letter_count+1
C.letter_count+=1可以写做letter_count++
D.函数能统计字符串中数字出现的次数
第5题:
5.We can______ books _______bookstore(书店).
A. sell ;to
B. buy ;from
C. sell ;from
D. buy ;to
第6题: