Which is true? Group of answer choices

Chemical reactions never involve changes in energy.

All chemical reactions release energy.

All chemical reactions absorb energy.

Some chemical reactions release energy and other reactions absorb energy, but all chemical reactions involve changes in energy.

Ascientist is conducting an investigation that involves water, silver, carbon dioxide, and oxygen gas which group of statements best describes all of the materials he is using in the investigation?

Under the soviet system, the government a. controlled all forms of communication. b. allowed newspapers to print whatever they wanted. c. controlled editorials but not the reporting of news. d. encouraged access to a wide variety of news sources. select the best answer from the choices provided a b c d

Which of the following words best matches this definition: the process in which the best adapted organisms survive and pass on their traits, while those that are not well adapted do not survive to pass on their traits. question 3 options: acquired selection natural selection artificial selection organic selection