Answer:
Forward chaining as the name suggests, start from the known facts and move forward by applying inference rules to extract more data, and it continues until it reaches the goal, whereas backward chaining starts from the goal, move backward by using inference rules to determine the facts that satisfy the goal.
Hydrogen bond. Although other ones are equally as important such as a dipole-induced dipole
North America and Europe lie entirely north of the equator. Almost all of Asia, most of Africa, and a part of South America are above the equator. Not sure if South America counts as 'mostly' though. That's up to you.
Answer:
Place a glowing splint in the test tube, and if it reignites, it could be oxygen. Place a burning splint into a test tube, and if it goes out, it could be carbon dioxide. Or, place carbon dioxide gas in limewater, and if it turns milky and gets chunks, it is carbon dioxide.
