The mountain range extending along the northern frontier of india was formed as the result of a collision of the indian subcontinent and what other continent?

This mountain range was formed by the collision of India, which sits on the Indo-Australian plate and Eurasia, that sits on the Eurasian plate. This collision led to the formation of the Himalayan mountain range, which houses the tallest mountain on earth, Mount Everest. This type of collision creates extensive fold mountain ranges. 

Geothermic gradient is the rate of increasing temperature with respect to increasing the depth in the earths interior. away from tech tonic plates boundaries, it is about 25-40 c/km (72-87 degrees f/mi) of depth near the surface in most of the world.