有如下的SQL语句: Ⅰ.SELECT sname FROMs,sc WHERE grade<60 Ⅱ.SELECT sname FROMs WHERE sno IN(SELECT sno FROM sc WHERE grade<60 Ⅲ.SELECT sname FROMs,sc WHERE s.sno=Sc.sno AND grade<60 若要查找分数(grade)不及格的学生姓名(sname),以上正确的有哪些? ( )
【简答题】Dick's grandmother is very rich. She has many shops. The old woman begins to learn drawing when she is sixty years old. And she loves it very much. She draws a lot of pictures for twelve years. One da...