in good condition

Vitamin C is also called ascorbic acid because it can prevent scurvy, so fresh vegetables lose less when eaten raw than cooked, and vitamin C is easy to oxidize in air and high temperature.

Therefore, the answer is: prevent suspicion; Vitamin c is easy to oxidize (or decompose) when heated; ?

② The heat generated by oxidative decomposition of fat per gram in human body is about 37.6kJ, glucose is about 16.4kJ, and protein is about 16.7kJ, and most of the energy is provided by fat.

So the answer is: grease;