What does the concept of scarcity explain? choose three answers.

The occupational safety and health administration requires employers to provide fall protection to construction workers who are working on surfaces with unprotected sides and edges feet or greater above the lower level.

He did chinese culture change during the warring states period

Sweater originally priced at $65 is on sale for 15% off. you also have a coupon that takes another $10 off. what percent of the original price do you pay?