Explanation : The conservative and theoretically accurate approach is to use bid prices
for long positions and ask prices for short positions. These are the prices at
which the positions could be closed
Explanation : The three main sources of return for a commodities investment are
collateral yield, roll yield or the convenience yield, and spot price return
Explanation : Main sources of return for a commodities futures contract are collateral
yield, roll yield (also called convenience yield), and spot price return