I presume you mean if you are outside where no structure on any kind is nearby.  In these cases, if possible find a ditch or low area and lie flat on your stomach in it.  This way you present the lowest profile possible to the winds and tornado.

2 How is a tornado formed?

Tornados form inside thunderstorms.  The ingredients necessary for the formation of thunderstorms are abundant low level moisture (moisture or high relative humidity below 5000 feet), upper level instability (usually cooler than normal air at 10,000 feet and above), and a “triggering action”, i.e., something that starts the air near the surface moving upwards (a cold front, afternoon heating, etc.).  While we still have much to learn about the formation of tornadoes, we do know very strong up and down motions in a thunderstorm are necessary for a tornado to form.  What actually starts these up and down drafts rotating is still under investigation.

3 How do tornadoes rotate?

See the answer to # 2.

4 How are hurricanes formed?

Hurricanes are formed when an area of low pressure over warm, tropical, ocean waters intensifies, causing the counter clockwise winds circling around the low to increase in speed.  Depending on favorable atmospheric conditions and the system remaining over it’s source of energy, the warm ocean waters, then it can become strong enough to reach hurricane status.  If the system moves over land away from the warm waters or over cooler ocean water, it will begin to weaken.  The stages of develop of a tropical weather system are...  tropical wave, tropical disturbance, tropical storm, and finally hurricane.

5 What precautions can someone take when there is an earthquake, tornado, hurricane, or volcano?

First, learn the safety rules for each of these disasters, don’t wait until they happen to try to decide what is the safe thing to do.  That could take up precious time that you need to protect yourself, loved ones, and your property.  For tornados and hurricanes, listen to the latest weather forecasts, watches, warnings, advisories for your area; know what each of them means, and be ready to take quick action.  

6 How can you measure wind speed in a hurricane and tornado? Is there a scale used?

Our best source of wind speeds in either a tornado or hurricane are instruments known as anemometers.  They measure the speed of the air moving past them.  The problem is that in tornados and hurricanes, the anemometers usually are blown by the strongest winds.  Doppler radar, which measures the speed at which the air moves towards and away from the radar antenna can be used to measure the wind speed, but it has to be in the right location.

Here are the scales used to classify the strength of tornados and hurricanes based on wind speeds:

Tornados (Fujita Scale)

F0.....40 - 72 mph
F1.....73 - 112 mph
F2.....113 - 157 mph
F3.....158 - 206 mph
F4.....207 - 260 mph
F5.....261 - 318 mph
F6.....319 mph and higher

Hurricanes (Saffir/Simpson Scale)
Category 1.....74 - 95 mph
Category 2.....96 - 110 mph
Category 3.....111 - 130 mph
Category 4.....131 - 155 mph
Category 5.....156 mph and higher

7 What is the most common windspeed of tornadoes in Texas? The United
States?

The majority of tornados in the U.S. are of the F0 to F2 strength storms.  The F3 and F4 storms are fewer in number, while the F5 and F6's are the rare tornado events.