26.Given below are two statements, labelled as Assertion (A) and Reason (R). In the context of the two statements, which of the following is correct ?Assertion (A) : The flash of lightning is seen before the sound of thunder is heared.Reason (R) : The sound of thunder is produced after the flash of lightning.

27.Given below are two statements, labelled as Assertion (A) and Reason (R). In the context of the two statements, which of the following is correct ?Assertion (A) : Helium is chemically an inert element.Reason (R) : Helium has its outer shell fully empty.

28.Domestic insects are controlled by

29.Given below are two statements, labelled as Assertion (A) and Reason (R). In the context of the two statements, which of the following is correct ?Assertion (A) : Red light is generally used as a caution symbol.Reason (R) : It has a longer wave length.

30.Given below are two statements, labelled as Assertion (A) and Reason (R). In the context of the two statements, which of the following is correct ?Assertion (A) : Most of the time individual rain drops hit the earths surface with constant velocities.Reason (R) : When an object falls through a viscous fluid, it attains a constant terminal velocity after sometime.