A lighthouse was 1,000 meters inland on a coast when it was built. After 100 years it was 10 meters inland. What most likely changed the relative position of the lighthouse? (3 points) a
Erosion of the lighthouse by the sand

b
Chemical weathering due to oxygen

c
Erosion of the beach by the ocean

d
Chemical weathering due to water

Explain why the aperture of the spherical mirror should be small compared to the radius of curvature of the mirror.

Which property of fossils allow scientists to determine the relative rock ages..

Arunner is jogging at a steady 3.6 km/hr. when the runner is 2.9 km from the finish line, a bird begins flying from the runner to the finish line at 14.4 km/hr (4 times as fast as the runner). when the bird reaches the finish line, it turns around and flies back to the runner. even though the bird is a dodo, we will assume that it occupies only one point in space, i. e., a zero-length bird. how far does the bird travel? (b) after this first encounter, the bird then turns around and flies from the runner back to the finish line, turns around again and flies back to the runner. the bird repeats the back and forth trips until the runner reaches the finish line. how far does the bird travel from the beginning? (i. e. include the distance traveled to the first encounter)