If you are enabled for margin trading, you can easily get a margin balance by simply buying more shares than you have money deposited for, or withdrawing money from the account in amounts higher than your cash balance. Ameritrade just acts like you have the money in both circumstances and allows the transaction.
4. Mosquitoes vary in their size: they reach 1.6-12.5 mm (0.5 inch). Fossil mosquitoes were even 5 cm (2 inch) long. 5. Mosquitoes do not bite, they suck. 1,200,000 mosquitoes would be necessary to completely drain the average human of blood. Well, unless you die before, but of irritation. 6. An experiment in the Canadian tundra found that people who bared arms, legs and torsos reported approximately 9,000 bites per minute from swarming, newly hatched mosquitoes.
Without question the answer is: the mosquito. Mosquitoes and the diseases they spread have been responsible for killing more people than all the wars in history. Even today, mosquitoes transmitting malaria kill 2 million to 3 million people and infect another 200 million or more every year. Tens of millions more are killed and debilitated by a host of other mosquito-borne diseases, including filariasis, yellow fever, dengue and encephalitis.