15-15×23-23
=15-10-23
=413（米）；
答：还剩下413米．
It is a rule in his family that ______ comes home earlier should cook the dinner for the family.
A．Anybody
B．who
C．who that
D．whoever
灯管与镇流器最佳匹配应达到哪些技术参数？
