In a boiler observations made were as:

Rate of feed water per hour \(=800 \mathrm{~kg}\)

Temperature of feed water \(=30^{\circ} \mathrm{C}\)

Steam pressure \(=12 \mathrm{bar}\)

Quality of steam \(=0.95\)

Coal consumption rate per hour \(=100 \mathrm{~kg}\)

Calorific value of coal \(=32,000 \mathrm{~kJ} / \mathrm{kg}\)

Mass of ash and unburnt coal \(=10 \mathrm{~kg} / \mathrm{h}\).

Calorific value of ash and unburnt coal \(=\) \(3,000 \mathrm{~kJ} / \mathrm{kg}\)

Quantity of flue gas/kg of coal \(=20 \mathrm{~kg}\)

Discharged gas temperature \(=350^{\circ} \mathrm{C}\)

Atmospheric temperature \(=25^{\circ} \mathrm{C}\)

Specific heat of flue gas \(=1.03 \mathrm{~kJ} / \mathrm{kgK}\).

Calculate:

(a) boiler efficiency

(b) percentage of heat loss in flue gas

(c) percentage of heat loss to ash and unburnt coal

(d) percentage of heat loss unaccounted for.