A:CuO→Cu(OH)2
B:KNO3→NaNO3
C:Cu→CuCl2
D:NaHCO3→NaCl
把实际15km的距离用3cm画在地图上,那么这幅地图的比例尺是____.
I hate it when she calls me at work—I'm always too busy to _____ a conversation with her.