In Bryophytes,which stage produces haploid,autotrophic gametes?

Which one of the following compounds gives aspirin on reacting with acetic anhydride in the presence of $H_2SO_4$?

$\frac{{\sqrt{2} - \sin \alpha - \cos \alpha }}{{\sin \alpha - \cos \alpha }} = $

Which one of the following statements is $NOT$ the property of light?

Which of the following is used for making optical instruments?

$A$ tension of $22 ~N$ is applied to a copper wire of cross-sectional area $0.02 ~cm^2$. The Young's modulus of copper is $1.1 \times 10^{11} ~N/m^2$ and the Poisson's ratio is $0.32$. The decrease in cross-sectional area will be: