Convert the temperature 288k to degree celsius

K is a unit for temperature Kelvins, and to calculate the temperature in Kelvin scale, we usually add the Celcius temperature by 273.15. 273.15 is a constant number and cannot be changed. By using Kelvins, calculating different numbers of science would be a lot more easier, as for example, only temperature in Kelvin scale can be directly proportional to gas pressure. 

Therefore, to find the temperature in Celcius from a temperature in Kelvin scale, we can minus 273.15 to the number given. 288-273.15 = 561
So, your answer is 14.85°C.

14.85 degrees Celsius

Your answer is water because there is combined mass of water found on, under, and over the surface of a planet. your answer is water.