Which of the following is the name given to a situation in which one fission reaction instigates exactly one more fission reaction?

a. a critical mass
b. a runaway chain reaction.
c. a controlled chain reaction.
d. a generation.

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The volume of a gas is halved during an adiabatic compression that increases the pressure by a factor of 2.5. what is the specific heat ratio? show the math steps .

An ionic compound can conduct electricity when a it is dissolved in water b its crystals are ground into powder c it is in solid form d it is heated to just below its melting point

Simon is writing a story about an astronaut whose spacecraft has been boarded by space pirates. the astronaut has her lucky penny in her hand behind her back as the space pirates break into the control room. she has just locked the controls so that the ship is accelerating in the direction of the control room’s ceiling. simon wants the astronaut to use the penny to hit a button on the control panel to turn off the lights and escape. the button is located a short distance behind and below the astronaut’s hands. how should simon use the theory of relativity to describe what the astronaut must do in order to hit the button?