Which of the following are good safety measures during a thunderstorm? a. talk on a phone with a cord. b. go inside a closed building. c. do not use any equipment that plugs into a wall outlet. d. carry an umbrella. e. stand in an open space.

 B. Go inside a closed building.

C. Do not use any equipment that plugs into a wall outlet.

A thunderstorm is a natural hazard, which is a type of storm. It is characterized by lightening, acoustic effects on the earth atmosphere that is called as thunder. The cumulonious cloud usually produces gusty winds, hail and heavy rainfall.

B. Go inside a closed building: This will prevent the person from high speed wind currents, lightening injury and hearing impairment due to thunder.

C. Do not use any equipment that plugs into a wall outlet: This is a preventive measure because thunderstorm is related with lightening and if sudden lightening falls over the house the effect of electricity will be intensified due to earthing.

compass can be used day and night, cloudy or sunny

pythagoras' theorem

square root (-5^2+9^2)

square root (25+81)

square root (106)

angle is tan^-1(9/5)

neg x, pos y