What are the three mechanisms for heat transfer and how do they differ?

A)Several years ago while participating in an early spring adventure race I had to cross a rapidly flowing stream that still had large chunks of ice floating in it.  The stream temperature was 0 °C. What mode of heat transfer do you think dominated? B)When solid food is place (example: a grilled cheese sandwich) onto a hot frying pan the food gets hot and cooks.  What do you think the dominant form of heat transfer? C)On a cold night friends love to huddle around the fireplace until we overheat .  What form of heat transfer do you think dominates in this situation?

There are three mechanisms by which heat can be transferred from one place to another. List these mechanisms and, for each one, provide (and briefly justify) an example of a kitchen appliance which uses the mechanism to heat food.

What is the definition of an “empty calorie”?