IMI I mean it. IMO In my opinion. IOW In other wordsâ¦ Related News: Amber Rose Accidentally Shared Her Phone Number To Her 3 Million Twitter Followers. IRL In real life. IUSS If you say so. J4F Just for fun. JFK Just for kicks. KC Keep cool. KHUF Know how you feel. KISS Keep it simple, stupid. KIT Keep in touch. KOTC Kiss on the cheek. KOTL Kiss on the lips. L8 Late
Best Answer: The crust or lithosphere is the coolest layer by far. It is what we live on. It is in the vicinity of 0 degrees C (varying with depth and location). The mantle is about 1,700 miles (2,750 km) thick.
The highest layer of earths atmosphere is the exosphere. The inner core has the most or highest amount of density (iron/nickel). I think its the core of the Earth with highest temperature with  6000 degree Celsius. The crust is the layer of the Earth that has the the lowest density. It depends a bit on what you consider being a part.