1) Calculate the amount of energy required to evaporate an ice cube having a mass of 45g.

I know that first it must go for solid to liquid which is E=mf and than from liquid to gas which is E=mLv .. can someone please show me how to do them... my test is tomorrow:(

Lf water= 3.3x10^5 J/Kg

water=4.2x10^3 J/Kg'C

ice= 2.1x 10^3 J/Kg'C

the other question i didnt get was:

2)An 80g mandarin orange is burned in bomb calorimeter. The 1.55 kg of water change in temperature from 21.0'C to 39.4'C. Calculate the energy per gram in the mandarin orange.

I would show you my attempt except its just ridiculous becuase i reallyyyy dont get it.

Your help is muchhhh appreciated.. i need help ASAP ...thank you