D.
The reading between 7N and 8N would have to be 7.5N. Answers A and B are much to small and answer C is way to big.
As per the question the color of laser light is given as red.
If we arrange all the electromagnetic waves in the decreasing order of frequency ,then the electromagnetic spectrum contains gamma ray as the first which is followed by all other electromagnetic waves according to their frequency.
The visible light ranges from 400 nm to 700 nm which contains sunlight i.e white colors with it's constituent colors starting from violet to red. The red color is the longest wavelength part of the visible region.
The wavelength of visible light is longer than ultraviolet wave but smaller than infrared radiation. Except the bisible region,the color of radiation is invisible to eye.
As per the question the color of emiited laser radiation is red .Hence it must lie in the visible region of the electromagnetic spectrum.
False, the Amazon River is in South America. It's in the countries Brazil, Colombia, and Peru.
