As per ___ guidelines, if the ratio of carbon dioxide (CO₂) and carbon monoxide (CO) in dissolved gas analysis is ___, it is predicted that the condition of paper insulation inside the transformer is poor.

There is one IEC guideline, number is IEC 599,
Statement of guideline is that "If the ratio of carbon dioxide and Carbon monoxide in Dissolve gas analysis test result is more than 11, it is predict that the condition of paper insulation inside the transformer is poor."
For healthy condition this ratio will be between 4 to 11.

A thermistor is inherently suitable for temperature measurement involving

Thermistors are ideal when measuring a single point temperature that is within 50°C of ambient.
If the temperatures are excessively high or low, a thermistor will not work.
Most thermistors work best in the range between -55°C and +114°C.
Sensitivity of thermistor is high.
Span value of thermistor is low.

The miniature circuit breaker (MCB) shown in figure is

If a 415 V, 50 Hz, star-connected, three-phase squirrel-cage induction motor is operated from a 415 V, 70 Hz supply, the torque that the motor can now provide while drawing rated current from the supply

Consider the following two statements and choose the correct answer.
Statement 1: The V-curves of a synchronous motor show relationship between armature current and supply voltage.
Statement 2: The plot of power factor against the field current of synchronous motor is known as inverted V curves.

The V-curves of a synchronous motor show relationship between Armature current (Ia) and Excitation current (If).
The Inverted V-curves of a synchronous motor show relationship between power factor (pf) and field excitation (If).

An electric potential field is produced in air by point 1 μC and 4 μC located at (-2, 1, 5) and (1, 3, -1) respectively. The energy stored in the field is