Can the temperature of an isolated system remain constant?

Can the temperature of an isolated system change?

Why does the total energy of an isolated system remains constant?

Assertion: Universe as a whole may be viewed an isolted system. Reason: Total energy of an isolated system remain constant or stretched.

Assertion: Universe as a whole may be viewed an isolted system. Reason: Total energy of an isolated system remain constant or stretched.

Assertion : If there is no external torque on a body about its centre of mass, then the velocity of the centre of mass remains constant. Reason : The linear momentum of an isolated system remains constant.

Assertion : If there is no external torque on a body about its centre of mass, then the velocity of the centre of mass remains constant. Reason : The linear momentum of an isolated system remains constant.

Statement-1: if there is no external torque on a body about its centre of mass, then the velocity of the center of mass remains constant. Statement-2: The linear momentum of an isolated system remains constant.

Satement-1: if there is no external torque on a body about its centre of mass, then the velocity of the center of mass remains constant. Statement-2: The linear momentum of an isolated system remains constant.