Question

Anu wants to boil water quickly in a test tube. On observing the
different zones of the flame, she is not able to decide which zone
of the flame will be best for boiling water quickly. Help her in
this activity.
NCERT Class VIII
Science - Exemplar Problems
Chapter 6. Combustion and Flame

Answer 1

outer most zone, cause it is the hottest zone of all the flame

Answer 2

Blue zone of the flame because it is the hottest zone