多选题Examine the description of the STUDENTS table: STD_ID NUMBER(4) COURSE_ID VARCHARD2(10) START_DATE DATE END_DATE DATE Which two aggregate functions are valid on the START_DATE column?（）ASUM(start_date)BAVG(start_date)CCOUNT(start_date)DAVG(start_date, end_date)EMIN(start_date)FMAXIMUM(start_date)
多选题
Examine the description of the STUDENTS table: STD_ID NUMBER(4) COURSE_ID VARCHARD2(10) START_DATE DATE END_DATE DATE Which two aggregate functions are valid on the START_DATE column?（）
A
SUM(start_date)
B
AVG(start_date)
C
COUNT(start_date)
D
AVG(start_date, end_date)
E
MIN(start_date)
F
MAXIMUM(start_date)
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