Which alga exhibits a haplo-diplontic life cycle?

Observe the following statements :
$I$. Bleaching powder is used in the preparation of chloroform.
$II$. Bleaching powder decomposes in the presence of $CoCl_2$ to liberate $O_2$.
$III$. Aqueous $KHF_2$ is used in the preparation of fluorine.
The correct combination is :

$A$ film of water is formed between two straight parallel wires of length $10\,cm$ each,separated by $0.5\,cm$. If their separation is increased by $1\,mm$ while still maintaining their parallelism,how much work will have to be done? (Surface tension of water = $7.2 \times 10^{-2}\,N/m$)

Identify the incorrect pair from the following:

The value of $k$,if $(1,2)$ and $(k,-1)$ are conjugate points with respect to the ellipse $2x^2 + 3y^2 = 6$ is:

If $\overrightarrow{E}$ and $\overrightarrow{B}$ are the electric and magnetic field vectors of electromagnetic waves,then the direction of propagation of the electromagnetic wave is along the direction of