Risk and disadvantages: Everyone knows that investment involves risk. But few people know that investors have two key disadvantages: (1) The percentage down is larger than the percentage up. A 50% gain can be eliminated by a 33% down. A 70% down will need to recover 333% just to break-even. (2) The speed of declining is faster than the speed of rising. Gains accumulated in years can be wiped out in months or weeks. Derivatives: Derivatives market is a financial casino. Ordinary people only have 50% chance of winning. When stock married put: However, the combination of stock and a put option...