Which of these is common to all chemical changes? a) a change of state occurs. eliminate b) a change of color occurs. c) a new substance is produced. d) heat is released into the air.

Listed below are the amounts of mercury (in parts per million, or ppm) found in tuna sushi sampled at different stores. the sample mean is 0.836 ppm and the sample standard deviation is 0.253 ppm. use technology to construct a 90% confidence interval estimate of the mean amount of mercury in the population.