841: LMNOP, is a semi-circle with centre at R and diameter LP, LSR and RQP are also semi-circles with centres at T and U and diameters LR = RP = 1/2 LP. The ratio of perimeters of LMNOP and LSRQP is
(a) 0.75 : 1
(b) 1 : 1
(c) 1 : 0.75
(d) 1.25 : 1
842: Which one of the following chemicals is responsible for the depletion of ozone layer in the atmosphere?
(a) Chlorofluorocarbons
(b) Nitrous oxide
(c) Sulphur dioxide
(d) Carbon dioxide
843: Assertion (A)
Eclipses do not occur on all full moon and new moon days
Reason (R)
The moon revolves round the earth in an elliptical orbit
(a) A and R both are incorrect
(b) A is correct but R is incorrect
(a) A and R are correct and R is the correct explanation of A
(b) A and R are correct but R is not the correct explanation of A
844: The film The Making of the Mahatma has been directed by
(a) Peter Ustinov
(b) Richard Attenborough
(c) Shyam Benegal
(d) Mira Nair
845: Assertion (A)
The First War of Indian Independence started in 1857
Reason (R)
The soldiers refused to use the greased cartridges
(a) if A and R both are correct and R is the correct explanation of A
(b) if A and R both are correct but R is not the correct explanation of A
(c) if A is incorrect but R is correct
(d) if A is correct but R is incorrect