Which of the following plants exhibits a haplontic life cycle?

Which of the following statements is incorrect for alkali metals?

The maximum energy in the thermal radiation from a hot source occurs at a wavelength of $11 \times 10^{-5} \text{ cm}$. According to Wien's law,the temperature of the source (on Kelvin scale) will be $n$ times the temperature of another source (on Kelvin scale) for which the wavelength at maximum energy is $5.5 \times 10^{-5} \text{ cm}$. The value of $n$ is

Which of the following is a polyamide?

Who was the first scientist to use the term 'virus' as a pathogen of infectious diseases?

$F_{pp}$,$F_{nn}$,and $F_{np}$ are the nuclear forces between proton-proton,neutron-neutron,and neutron-proton respectively. Then the relation between them is: