Answer:
1964
Explanation:
It was discovered in 1964 when a pair of Geiger counters were carried on board a sub-orbital rocket launched from New Mexico.
Neither of the technicians are correct.
<h3>Who is a technician?</h3>
A technician simply means an individual who looks after the technical equipments in a company.
In this case, the teeth of the synchronizer are not rounded, the synchronizer can be reused. This shows that he is incorrect likewise technician B.
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