Refrigeration and Air Conditioning
A one tonne refrigerating machine means that

One tonne of ice when melts from and at 0° C in 24 hours, the refrigeration effect is equivalent to 210 kJ/min
One tonne is the total mass of machine
One tonne of water can be converted into ice
One tonne refrigerant is used

ANSWER DOWNLOAD EXAMIANS APP

Refrigeration and Air Conditioning
Environmental protection agencies advice against the use of chlorofluorocarbon refrigerants since

These react with ozone layer
These react with oxygen and cause its depletion
These react with plants and cause greenhouse effect
These react with water vapour and cause acid rain

ANSWER DOWNLOAD EXAMIANS APP