Each of the three known isotopes of hydrogen has blank protons in the nucleus

An engineering team designs a new rocket that is faster and lighter than any other model being produced. however, the materials end up being so expensive that no company can afford to buy them. which step of the engineering process should have addressed this problem? a. know the background. b. evaluate the results. c. identify a need. d. do the work.

Which answer lists the fundamental forces in order from strongest to weakest

List four observations that indicate that a chemical reaction may be taking place