instruction:
In this task, find the most appropriate number to replace the blank (indicated with _ ) and express it in words.
question:
World population continues to rise, even as a few countries move toward _ growth.
answer:
zero


question:
Most people stay in a nursing home for less than _ years.
answer:
four


question:
Water is visualized as occupying the center of a tetrahedron, a solid with _ faces.
answer:

four