How much X-rays and ElectroMagnatic ray can cause cancers?

Answer:
Very very very minimal.

For someone to get cancer from those, you need to be exposed on very regular basis or be exposed at a high level.

That is why radiology techs and radiologists have to wear a tag to see how much radiation they are exposed each year. That is also why the property (land) near powerlines are not developed for residential (usually) - because of the electormagnetic field generated from running electricity.

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