The very poultry in the coop Began to pine away and droop— The cock was first to go; And glad we were on all our parts, He used to damp our very hearts With such a ropy crow.

The empty set has a cardinality of zero.

Even a small camber one way caused the whole outfit to list alarmingly.

Metaphosphoric acid gives a white precipitate with nitrate of silver solution; orthophosphoric acid does not give any, save on the addition of an alkali, and the precipitate then produced is yellow.