How do you know that volume of a diamond is 15.1g

They are like other investigations? say there was a murder u have to do blood test and finger prints which run through a lab. 

Ans. : frostbite is when exposure to cold temperatures causes freezing to the skin or other tissues. it most commonly affects the hands, feet, and face. the longer areas are exposed to cold, typically the worse the frostbite. the water temperature used for rewarming a frostbitten part should be : (102 -105) f degrees.