【もう六月】宅浪スレpart14【まだ六月】at KOURI【もう六月】宅浪スレpart14【まだ六月】
- 暇つぶし2ch895:大学への名無しさん 09/06/02 09:47:09 v0dIQAVbO Why is it that a lamp hanging in the cathedral and moving in the swirling currents of air always takes the same time to complete its swing, however short or long that swing may be?