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A physics question, our teacher gets mad at us and assigns insane problems for homework. Please help I have no idea where to go with these.

1) A traveling submarine is 325 m horizontally out from the shore and 115 m beneath the surface of the water. A laser beam is sent from the sub so that it strikes the surface of the water at a point 205 m from the shore. If the beam strikes the top of a building standing directly at the waters edge, find the height of the building. (Hint: to determine the angle of incidence, consider the right triangle formed by the light beam, the horizontal line drawn at the depth of the sub, and the imaginary line straight down from where the beam strikes the surface of the water.)

2 ) A laser beam traveling in air strikes the midpoint of one end of a slab of material at a 50 degree angle. The index of refraction of the slab is 1.48. The length is 42.0 cm and the width 3.1 cm. Determine the number of internal reflections of the laser beam before if finally emerges from the opposite end of slab.

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by subtracting the horizontal distance of submarine from surface and the dist between the building and point off contact of laser with water we get the distance of the vertical projection of submarine from the point where laser touches water as 120 ( 325-205)

the triangles formed by buliding and the former triangle formed by submarine are similar so,
building's height/ 205=115/125

building's height=188.6 mts

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This was wrong, thank you anyways.
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