C$)$ Which is the safest investment? Why do you think so$?$

The third investment is safest because in the long run, the risk of losing any money is the least. The second investment is safest because it has the greatest expected value. The second investment is safest because there is a $60\%$ chance of making money, which is higher than with the first and third investments. The first investment is safest because there is a $10\%$ chance of making $$5,000,000.$

D$)$ Which is the riskiest investment? Why do you think so$?$

The third investment is the riskiest because it has the greatest chance of not returning any money or losing money. The third investment is the riskiest because it only has a $10\%$ chance of returning any money. The second investment is the riskiest because there is a $40\%$ chance of making $$1,000,000$ and a $40\%$ chance of losing $$1,000,000,$ so the result would be no change in the investment. The first investment is the riskiest because it has the greatest chance of losing money and the lowest expected value.

E$)$ Which investment has the highest expected return, on average?

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