Which nutrient class provides the highest energy per gram?

Lipids (fats)

Who portrayed Ron Weasley in the "Harry Potter" movie series? The city of Casablanca is located in what country? Which country claims it is the "Home of Santa Claus" and has a village named Santa Claus Village? Which food has a higher potassium content per gram than bananas? What microscopic organisms can cause diseases and infections?