What physical features both protected Egypt from invasion and prevented
it from expanding westward?

the Egyptians were protected from invasion because of their geographical features. Also, the eastern and western deserts prevented invaders from the east and west.

b.) plain  

hope this

the correct answer is blue and green.

a visible spectrum is electromagnetic spectrum color that can be seen by a normal human being by a single wavelength of light. the visible light spectrum is the range of wavelengths that make up visible light. the visible light spectrum passes through a prism enabling the rainbow reveals all the colors in the spectrum. these range from red, orange, yellow, green, blue and violet.