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Author Question: 21. In positron emission tomography, when positrons come into contact with a free electron, they are ... (Read 93 times)

jazziefee

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21. In positron emission tomography, when positrons come into contact with a free electron, they are annihilated. This annihilation produces two byproducts
 
  a) 2 photons
  b) 2 protons
  c) 2 electrons
  d) 2 positrons

Question 2

What does the half-life of a gamma radiation-emitting tracer refer to?
 
  a) The half-life is the time it takes for the substance to reach a non radioactive state
  b) The half-life is always 3 days
  c) The half-life is the amount of time that the substance requires to begin emitting gamma rays
  d) The half-life is the amount of time that it takes for a substance to reach a radioactive state



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apple

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Answer to Question 1

ANSWER: A

Answer to Question 2

ANSWER: A




jazziefee

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Reply 2 on: Jun 22, 2018
:D TYSM


cassie_ragen

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Reply 3 on: Yesterday
Gracias!

 

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