What does a Fire Brigade do when it arrives at a place where a building is on fire ?

What is fire foam?

Why does a gun recoil When a bullet is fired ?

Rajan constructed a small house. He used good quality and well insulated copper wires for wiring. He also used good quality switches, sockets and plugs. However, had a very old room heater. On one winter night, Rajan was sleeping in a closed room with his family with the room heater switched on. During sleep, Rajan felt suffocated and woke up to see the room heater on fire. Rajan's son Arvind got up quickly and put off the main switch. Arvind also made a telephone call to Fire Brigade. The Fire Brigade men reached quickly and extinguished fire in the room. Rajan and his family thanked the firemen. (a) What was the cause of fire in Rajan's house ? (b) Name the safety device which was missing in the electric wiring of Rajan's house ? (c) How could the above device prevent fire in Rajan's house ? (d) What values are displayed by Arvind in this whole incident ?