When one scientist repeats another scientist's experiment, he or she is probably trying to a. show that he or she can do a better job b. practice how to do a new experiment c. confirm the work of the other scientist d. teach a new procedure to students

C. confirm the work of the other scientist

Explanation:

In formulating an acceptable hypothesis to back up a scientific finding, a scientist must make sure his experimental procedures are repeatable and falsifiable.

Repeatable experimental procedures allows for other scientists to critique a work. This can further throw more light into a finding and elevate the status of an observation to that of a theory or law. Other scientists repeats experiments in order to confirm the work of others if they are truly what they say they are.

periodic trends is an atom that gets larger as the number of electronic shells increase, the radius of atoms increases as you go down a certain group in the periodic table of elements. in general, the size of an atom will decrease as you move from left to right of a certain period.

if you mean hydrogen and oxygen then water is the product