Which of the following groups of organisms can interbreed?

At a given temperature,the pressure of an ideal gas of density $\rho$ is proportional to

In angiosperms,the functional megaspore develops into:

$A$ simple harmonic progressive wave is given by $y = y_0 \sin 2 \pi (nt - \frac{x}{\lambda})$. If the wave velocity is $\left(\frac{1}{8}\right)^{\text{th}}$ of the maximum particle velocity,then the wavelength is:

If $y$ is a function of $x$ and $\log(x+y)=2xy$,then the value of $y'(0)$ is

$\operatorname{sech}^{-1}(\sin \theta)$ is equal to