Answer the questions by using the suggested key - words in the answers of your own

1. Why does air -motion take place?

because, there exist, the temperature difference, between the heating or cooling elements, the air around.

2. What apparatus are used to produce air-motion?

to produce air-motion, heating or cooled apparatus with a fan.

3. What does air-motion do?

to distribute, the heated or cooled air, within the room.

4. What equipment do air-conditioning systems include?

air-conditioning systems, include, fans, filters, humidifiers, automatic controls, air washers, heat batteries.

Read the sentences and answer the questions.

1. Air-conditioning is the treatment of the air in the building so as to make it more suitable for industrial processes, more comfortable and healthful for men.

What do we understand by air-conditioning?

2. The factors which are of importance in air-conditioning are temperature, humidity, air-motion, air distribution, dust, bacteria, and toxic gases.

What factors are important in air-conditioning?

3. No air-conditioning system deserves the name air-conditioning unless it controls three factors: temperature, humidity, and air-motion.

What are the most important factors in air-conditioning?

4. Air-motion is caused by heating and cooling apparatus with a fan.

What is heating and cooling apparatus which causes air-motion supplied with?