Sodium-21 Will Emit Positrons, Each Having an Energy of 4

question 5

Multiple Choice

Sodium-21 will emit positrons, each having an energy of 4.0 × 10^-13 J. What is this energy in MeV? (1 MeV = 1.602 × 10^-13 J)

• A) 4.0 × 10^-7 MeV
• B) 2.5 MeV
• C) 40 MeV
• D) 2.5 × 10⁶ MeV
• E) 2.5 × 10^-6 MeV

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