(a)

Find .

Observe the graph of the function :

As approaches to , the limit of the function is approaches to .

Thus, .

The point is known as melting point.

(b)

Observe the graph of the function :

As approaches to , the limit of the function is approaches to .

Thus, .

The limit represents the room temparature.

(c)

No.

Because, the glass removed from the kiln brings an amount of heat(i.e, energy) in the system glass + room

such that the final  (equilibrium) temparature is greater that the initial room temparature.

Since however, the room is much bigger, practical infinite, the equilibrium temparature approaches,

in the limit, the previous room temparature.

(a) , the point is known as melting point.

(b) and it represents the room temparature.

(c) No.