Part c because of this temperature difference, the magnitude of the entropy lost by the surroundings is the magnitude of entropy gained by the gas during a real isothermal expansion.

less than

Explanation:

We know that entropy of the system is zero for the revertible process and it is positive for irreversible process.

Isothermal process the work is done by the gas and there is heat loss due to heat loss the entropy of the system decreases

So in fill in the blanks there will be less than as the entropy  decreases in isothermal process

continuous conducting path for current, power supply

the components of a vector are the parts of the vectors that are to each other.

b perpendicular