13. The great pyramid was attributed to whose King of Egypt?

Aray diagram for a refracted light day is shown. what does the dashed line represent

Abeam of electrons with of wavelength of 7.5 x 10-6 m is incident on a pair of narrow rectangular slits separated by 0.75 mm. the resulting interference pattern is projected onto a screen 10.0 m from the slits. what is the separation of the interference maxima in the resulting interference pattern?

Ineed the answer to question 1 , i’m desperate