2751: Where does exchange of gases (O2 and CO2) take place in our lungs ?
(a) Alveoli
(b) Bronchi
(c) Pleura
(d) Trachea
2752: With reference to forced labour (Vishti) in India during the Gupta period, which one of the following statements is correct?
(a) It was considered a source of income for the State, a sort of tax paid by the people.
(b) It was totally absent in the Madhya Pradesh and Kathiawar regions of the Gupta Empire.
(c) The forced labourer was entitled to weekly wages.
(d) The eldest son of the labourer was sent as the forced labourer.
2753: Which one of the following Himalayan passes was reopened around in the middle of the year 2006 to facilitate trade between India and China ?
(a) Shipki La
(b) Jara La
(c) Chang La
(d) Nathu La
2754: Acid rain is caused by pollution of environment by:
(a) Carbon dioxide and nitrogen
(b) Carbon monoxide and carbon dioxide
(c) Ozone and carbon dioxide
(d) Nitrous oxide and sulphur dioxide
2755: Which of the following pairs is/are correctly matched ? Spacecraft Purpose
1. Cassini -Huygens Orbiting the: Venus and transmitting data to the Earth
2. Messenger: Mapping and investigating the Mercury
3. Voyager 1 and 2: Exploring the outer solar system
Select the correct answer using thecode given below:
(a) 1 only
(b) 2 and 3 only
(c) 1 and 3 only
(d) 1, 2 and 3