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Around faucet handle is part of a(n) a. lever b. screw c. inclined plane d. wheel and axle

Which of the following is part of the explanation or description of electromagnetic waves? (select all that apply) a. electrically charged molecules in a medium transfer their energy to nearby electrically charged molecules. b. a changing electric field causes a changing magnetic field. c. magnetic molecules in a medium transfer their energy to nearby magnetic molecules. d. a changing magnetic field causes a changing electric field.

How many electrons does each element require in its valence shell to become stable?