Explanation:

We assume kinetic and potential energy changes are negligible and there is no work interactions.
a) Taking tank as a system, The energy balance can be define as


The mass balance could be written as

The final pressure in the tank could be defined as following

from standard steam table we know at

b)
From steam table at


initial mass in the tank could be define as

Final mass in the tank could be define as

The amount of steam that has entered the tank

c)
The internal energy in final state could be defined as following

The heat transfer could be defined as following

Tectonic plates under the ground ,either go on top of each other or crash.
True, charge can not be created or destroyed, only transferred