A geological sample is found to have a pb-206/u-238 mass ratio of 0. 337/1. 0. Assuming there was no pb-206 present when the sample was formed, how old is it? the half-life of u-238 is 4. 5 × 109 years.

Arealtor is studying the graph above, which shows the expected value of properties in her area over the next 24 years. if t represents the number of years after 2014, in what year should the increase in property values start to slow down? a. 2008 b. 2018 c. 2022 d. 2030

Which of the following must happen in order for productivity to increase? a. production levels remain unchanged while inputs increase. b. production levels rise while inputs decrease. c. production levels fall while inputs increase.

What are the two main purposes of edgar allen poe’s, “the masque of the red death? ”