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What is another way name for bd? cf, bd, cf, be

Apopulation of bolts has a mean thickness of 20 millimeters, with a population standard deviation of .01 millimeters. give, in millimeters, a minimum and a maximum thickness that includes 68% of the population of bolts.

Layer r contains a well-known index fossil that is 100 million years old. based on this information and the principle of superposition, a. layers t and m are older than 100 million years, and layers x and g are younger than 100 million years. b. layers t, m, x, and g are all older than 100 million years. c. layers t and m are younger than 100 million years, and layers x and g are older than 100 million years.