Answer:
The three basic items to make an electromagnet are a source of current, conducting wire, and a metallic core. Electromagnetic is a type of magnet which is formed with the help of electricity.
When the current is allowed to pass through the wire and the metallic core, the magnetic field is generated around the metallic core and when the current is turned off, the metallic core losses the property of magnetism.
Answer:
Collapse of seals, sea lions & sea otters in North Pacific triggered by overfishing of great whales. ... Lead author Alan Springer (University of Alaska, Fairbanks) and his co-authors propose that the decimation of great whale (baleen and sperm) populations by overfishing removed a major source of food for killer whales.
Explanation:
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