绩效目标的类型有那些？
参考答案：
短期目标、长期目标、常规或维持目标、问题解决目标、创新目标、个人发展目标
Betty stayed at home and studied _____ exams last weekend. [ ]
A. with
B. for
C. on
D. about
φ12圆钢每米重（）kg。
