find change in energy of a 550 mL cup cooling from 88°c to 10°c. the liquid also has a P of 1.38g/mL

Plz me get these answer dubble cheak ur answer plz ppl i need it right

Margaret wants to make an orange flavored drink by stirring powdered drink mix into a glass of water. she doesn't like drinks that have small clumps of powdered solid in them, so she wants the drink to be a perfect solution. what factors should margaret not consider when deciding how much powder to add to her glass of water?

According to each substances heat of fusion, which of the items below requires more heat to be added per gram of substance to go from solid to liquid? silver sulfur water lead