Two Vectors Lie with Their Tails at the Same Point

question 22

Multiple Choice

Two vectors lie with their tails at the same point.When the angle between them is increased by 20° their scalar product has the same magnitude but changes from positive to negative.The original angle between them was:

• A)0°
• B)60°
• C)70°
• D)80°
• E)90°

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Definitions:

Vitamins

Organic compounds that are essential for normal growth and nutrition and are required in small quantities in the diet because they cannot be synthesized by the body.

Minerals

Inorganic nutrients ingested as salts dissolved in food and water.

Free-Living Flatworms

Flatworms that are not parasitic and live independently in various aquatic or moist terrestrial environments.

Pharynx

The membrane-lined cavity behind the nose and mouth, connecting them to the esophagus.