Elephant are my favorite animal
In the above examples, the only one that is not an example of speed is the option:
"6 miles per hour north". A speed doesn't have a direction added to it. If a statement has a direction added to it, it's velocity, not speed. Speed is a scalar quantity. In other words, it is the rate at which the object covers the distance. Speed does not care about direction. It is also not aware of direction. Velocity, on the other hand, is aware of direction and of speed.
A. A UNIT OF ENERGY SUPPLIED BY FOOD.
A calorie is a unit of energy. Historically, scientists have defined "calorie" to mean a unit of energy or heat that could come from a variety of sources, such as coal or gas. In a nutritional sense, all types of food — whether they are fats, proteins, carbohydrates or sugars — are important sources of calories, which people need to live and function.
