What is the purpose of the underlined sentence in the passage? A
to prove that fossil fuels are responsible for climate change

B
to explain why Earth’s average yearly temperature is rising

C
to clarify that greenhouse gases are not always bad

D
to provide a quote from a climate-change expert

Which best describes why nh4+ can form an ionic bond with ci-?

Over the last 90 years, scientists have added to the body of evidence supporting the big bang theory. what is the latest piece of evidence discovered in 2014?

Astable electron arrangement for an atom is one that does not easily change. how is this arrangement arrived at? a. valence electrons are transferred or shared to create a full outer shell of electrons. b. valence electrons are discarded into space to create a full outer shell of electrons. c. protons (positive charge) pair with valence electrons (negative charge) to create a strong bond. d. outer shells with valence electrons are transferred or shared.