What was the age distribution of prehistoric Native Americans? Extensive anthropological studies in the southwestern United States gave the following information about a prehistoric extended family group of 83 members on what is now a Native American reservation. For this community, estimate the mean age expressed in years, the sample variance, and the sample standard deviation. For the class 31 and over, use 35.5 as the class midpoint. (Round your answers to one decimal place.)

Scientists observed a rock stratum and discovered some fossils. the image shows the fossils they discovered. what can you interpret from the image? an illustration showing layers rock with fossils embedded in some rock layers1. the dinosaur and the mammoth existed after the trilobites.2. the dinosaur and the armored fish existed before the trilobites.3. the trilobites and the armored fish died before the dinosaur.4. the trilobites and the armored fish were born after the dinosaur.5. the early mammoth is older than the trilobites.

Which statement best describes gravity? it is the force that repels only very small objects. it is the force that acts between objects with zero mass. it is the force that sometimes acts only on very large objects. it is the force that acts between any two objects in the universe.

In 1999, the u.s. announced trade sanctions worth $116.8 million, targeting goods from france, germany, italy and denmark. the sanctions were in retaliation for a ban on u.s. hormone-treated beef by which organization?