Electricity 1a

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Across
  1. 2. a ??? can be used to open or close a circuit
  2. 6. batteries are ??? sources of electricity
Down
  1. 1. electrical charge flow from the negative terminal to the ??? terminal
  2. 3. electrical charges flow through an electric ???
  3. 4. electrical energy involves the flow of ???
  4. 5. an electric circuit with gaps is a/an ??? circuit