a. Ultraviolet radiation
b. Sun’s ultraviolet (UV) radiation
c. Both a & b
d. None of these
a. Tin
b. Zinc
c. Copper
d. None of these
a. for coagulation of mud particles
b. to kill bacteria
c. to remove salts
d. to remove gases
a. Abu-Mansur Daqiqi
b. Abu Al-Qasim Firdausi
c. Khosrau II
d. None of these
a. 2 August 1990
b. 17 January 1991
c. 28 February 1991
d. None of these
a. The Itaipu Dam
b. Grand Coulee Dam
c. Â Three Gorges Dam
d. None of these
