Which substance can not be decomposed by a chemical change?
(1) ammonia (3) propanol
(2) copper (4) water

Which of the following best describes the formation of plasma?

What is the polyatamic ion of borate

Mike and mitchell decide to have a foot race. they mark off a stretch of 100 yards, and recruit cindy to work the stopwatch. after running the race and looking at the results, cindy declared that mitchell was the fastest. so how did the boys times compare?