群体质量
参考答案：反映群体发育优劣的多项性状指标的优化值的综合状况。
Faye's fondest memory is of last year, ____ the club gave a tea party for her birthday.[ ]
A. that
B. which
C. where
D. when
弦锤击弦后被挡接木托住时与弦的距离通常为（）。
A.20mm-30mm
B.2mm-4mm
C.12mm-15mm
D.5mm-10mm
