whe volume of an ideal gas changes from 0.40 to 0.55 m3 although its pressure remains constant at 50 000 Pa. What work is done on the system by its environment

Protein provides 4 calories per gram. mary is on a diet that requires her to eat at least 40 grams of protein each day. she's eaten 152 calories of protein today. howmuch more protein does mary need to eat to meet her goal