Radiotracers are used to detect medical problems safely.

I would say false...

excess of x-radiations on our body is not good for health

Radiotracers are chemicals that are placed into the body where one or more of their atoms are radioactive. Since these often give off highly penetrating radiation such as gamma waves, the effect of the radiation on the body is minimal as it mostly passes out of the body. This radiation can then be detected, and is used to monitor blood flow throughout the body as this is how the chemicals travel. Therefore the statement is true.
Hope this helps! Also I hate to be that guy but if you could please make this the brainliest answer I would really appreciate it :)

Wind will blow from one direction to another.

The correct answer is "atomic weight".