Which are the most primitive types of organisms?

The differential equation of the family of parabolas with vertex at $(0, -1)$ and having axis along the $Y$-axis is

For a body moving in a circular path,what is the condition for no skidding if $\mu$ is the coefficient of friction?

Which of the following taxonomic categories of the housefly is incorrectly matched?

$3.2$ moles of hydrogen iodide were heated in a sealed bulb at $444 \, ^oC$ until the equilibrium state was reached. Its degree of dissociation at this temperature was found to be $22 \%$. The number of moles of hydrogen iodide present at equilibrium are:

The most general value of $\theta$ which satisfies both the equations $\tan \theta = -1$ and $\cos \theta = \frac{1}{\sqrt{2}}$ is