Study of lunar soil. Meteoritics (Mar. 1995) reported the results of a study of lunar soil evolution. Data were obtained LO9 from the Apollo 16 mission to the moon, during which a 62-cm core was extracted from the soil near the landing site. Monomineralic grains of lunar soil were separated out and examined for coating with dust and glass fragments. Each grain was then classified as coated or uncoated. Of interest is the “coat index”—that is, the proportion of grains that are coated. According to soil evolution theory, the coat index will exceed .5 at the top of the core, equal .5 in the middle of the core, and fall below .5 at the bottom of the core. Use the summary data in the accompanying table to test each part of the threepart theory. Use a = .05 for each test.

Location (depth)
Top (4.25 cm)
Middle (28.1 cm)
Bottom (54.5 cm)
Number of grains sampled 84 73 81 Number coated 64 35 29