An unknown spectrum has a red line at 653 nm and a violet line at 450 nm. What angular separation between these two spectral lines is obtained with a diffraction grating that has 3,500 lines/cm

that tool is called an altimeter which measures your altitude which can be used to tell which atmosphere you are currently in, including the stratosphere.

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according to jean piaget, in what stage of cognitive development are children able to understand conservation task?

b. preoperational

just took it