1. which layer of the earth do convection currents occur in? (1pt)

2. explain how these convection currents cause the crust of the earth to
move. (5pts)

directions: read the lesson tab in the lesson to answer questions 3 through 8

3. according to the theory of continental drift, what did the earth’s continents look like 255 million years ago? what is the name of this landmass? (2pts)

4. what is the petoskey stone, and where was it found? (2pts)

5. how does the petoskey stone prove the theory of continental drift? (5pts)

6. how does the shape and size of the continents today support the theory of continental drift? (5pts)

7. explain how looking at the magnetism of certain rocks support the idea that the continents have moved and changed over time. (5pts)

People with normal vision cannot focus their eyes underwater if they aren't wearing a face mask or goggles and there is water in contact with their eyes. in a simplified model of the human eye, the aqueous and vitreous humors and the lens all have a refractive index of 1.40, and all the refraction occurs at the cornea, whose vertex is 2.60 cm from the retina.with the simplified model of the eye, what corrective lens (specified by focal length as measured in air) would be needed to enable a person underwater to focus an infinitely distant object? (be careful-the focal length of a lens underwater is not the same as in air! assume that the corrective lens has a refractive index of 1.62 and that the lens is used in eyeglasses, not goggles, so there is water on both sides of the lens. assume that the eyeglasses are 2.05cm in front of the eye.)