Base load power plants are
$$P.$$ wind farms
$$Q.$$ run-of-river plants
$$R.$$ nuclear power plants
$$S.$$ diesel power plants

Determine the correctness or otherwise of the following Assertion (a) and the Reason (R).
Assertion (A): Fast decoupled load flow method gives approximate load flow solution because it uses several assumptions.
Reason (R): Accuracy depends on the power mismatch vector tolerance.

Consider a $$HVDC$$ link which uses thyristor based line commutated converters as shown in the figure. For a power flow of $$750$$ $$MW$$ from System $$1$$ to System $$2,$$ the voltages at the two ends, and the current, are given by: $${V_1} = 500\,kV,\,\,{V_2} = 485\,kV\,\,$$ and $$\,{\rm I} = 1.5\,kA.\,\,$$ If the direction of power flow is to be reversed (that is, from System $$2$$ to System $$1$$) without changing the electrical connections, then which one of the following combinations is feasible?

A moving average function is given by $$y\left(t\right)=\frac1T\int_{t-T}^tu\left(\tau\right)d\tau$$. If the input u is a sinusoidal signal of frequency $$\frac1{2T}Hz$$, then in steady state, the output y will lag u (in degree) by ________.