Which type of valve guide is most often used in a cast-iron head? a. bronze b. thin wall sleeve c. powdered metal d. integral

What is the american psychological association’s ethical principle of psychologists and code of conduct based upon? a. the work of a dozen world-renowned philosophers and ethical savants. b. the feedback of thousands of psychologists and their ethical struggles. c. the regulatory power and authority of the united states constitution. d. the hippocratic rules and guidelines of medical practitioners and surgeons. select the best answer from the choices provided a b c

How much hazardous chemical waste is produced per year in the us? a) 25 million metric tons b) 100 million metric tons c) 250 million metric tons d) 700 million metric tons e) 950 million metric tons

When did human beings first arrive in the americas? how did they get there?