heat! please help (problem solving)how much heat is needed to change...?

Question

how much heat is needed to change once gram of ice at 0 degrees celsius to steam at 100 degrees celsius?

Answer 1

the ice is to be converted into water at 0 degrees
it requires 80 cal
then this water has to be converted into water at 100 degress
this requires 100 cal
then it should converted into stream at 100 degrees
this requires 540 cal
total heat required=80+100+540
=720 cal