No. Tornadoes occur naturally.
tornadoes do a lot of damage. it can leave people in devistation, cost a lot of money and kill people.
it is unknown. global warming may increase or decrease tornadoes, more studies need to be done to determine this.
No. planes do not make tornadoes
No. Tornadoes are very powerful storms, and while it's possible for a tornado to kill people, it is not inevitable. Many tornadoes kill no one at all. In fact, only about 2% of tornadoes are killers. However, the tornadoes that make the news and get the headlines are the ones in which people ARE killed and injured. The prime adage of the news editor is "If it bleeds, it leads!"
They make buildings collapse on them and causes flying debris to hit them.
Some have propose that global warming may cause and increase in the number of tornadoes and number of strong tornadoes, but so far there has been no substantial evidence of that. Aside from that possibility it is unlikely that tornadoes are any stronger or more frequent as a result of human activity. However death tolls and injuries may be higher as a result of practices such as building houses without basements and trailer parks in tornado prone areas. These do not affect the tornadoes themselves, but leave people who live in such places more vulnerable.
You can warn people about tornadoes by posting a weather warning on tv or radio. I agree with that, but, not all people have radio, or television. Just to be safe, make sure your neighbors are aware of warnings, and help them to safety.
People have died from tornadoes in many cities.
They can't. People cannot prevent tornadoes.
The number of people killed by tornadoes is so low that an "out of 10" comparison doesn't make sense. You'd need to get into the "out of ten millions" or even into the "out of hundred millions" Before you'd get numbers that make sense.
There is no way of saying for certain. The apparent increase in tornado activity over the past 60 or so years is due largely to our improved ability to detect and confirm weaker tornadoes. U.S. statistics for stronger tornadoes show no overall increase in activity.