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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.

Embryos of different species look very similar, which shows that the organisms share a ancestor.

What is the mass of sodium in 3 moles of sodium chloride