In which group of organisms does the cell wall form two thin overlapping shells that fit together?

Which of the following statements are correct about slime moulds?
$(i)$ Its thalloid body,Plasmodium,has pseudopodia for locomotion and engulfing organic matter.
$(ii)$ During unfavourable conditions,Plasmodium differentiates and produces fruiting bodies,sporangia.
$(iii)$ Spores possess no true cell wall.
$(iv)$ They are dispersed by air currents.
$(v)$ Being extremely resistant,spores survive for many years.
$(vi)$ Plasmodium can grow up to several feet.
Choose the correct answer from the following options:

Characteristic spores of diatoms are

In ...............,cilia help in the movement of food through the cytopharynx and in locomotion.

Osmoregulation in $Paramecium$ is a function of . . . . . .

The function of the contractile vacuole in $Amoeba$ is: