Positrons are spontaneously emitted from the nuclei of
(1) potassium-37 (3) nitrogen-16
(2) radium-226 (4) thorium-232

Option (1) is the correct answer.

Explanation:

A positron is represent by the symbol .

For example,

The decay reaction is as follows.

The reaction will be as follows.

Therefore, we can conclude that out of the given options positrons are spontaneously emitted from the nuclei of potassium-37.

a. a clone will be physically identical to the original, but won’t be genetically identical

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