A.3π/4 B.3π/2 C.π/4 D.π/2 E.(3+π)/2 75° in radian measure is A.π/75 B.75/π C.5π/12 D.12π/5 E.π/30 3.An arc PQ subtends an angle 60° at the centre O of radius 3 cm. The area of the sector POQ is A. 270

(d) Hydrogen sulphide has weak ………. properties. (e) Halogens have essential electronic structure of ………. . (f) In the reaction with ammonia, boron trifluoride behave as an ………. . (g) The IUPAC name of