The complex $[Pt(py)(NH_3)(Br)(Cl)]$ will have how many geometrical isomers?

The synthesis of crotonaldehyde from acetaldehyde is an example of $.......$ reaction.

The resistance of a wire is $R$. It is bent at the middle by $180^{\circ}$ and both the ends are twisted together to make a shorter wire. The resistance of the new wire is

For $a, b, h > 0$,if the slope of one of the lines represented by $a^2 x^2 + 2hxy + b^2 y^2 = 0$ is twice that of the other,then the value of $\frac{h}{ab}$ is

The organelle associated with aerobic respiration is:

If $\lim _{x \rightarrow \infty}\left(\frac{x^2+x+1}{x+1}-ax-b\right)=4$,then