Floridean starch is the reserve food material in which of the following?

$A$ research student collects and observes some algae. The cells contain both chlorophyll $a, b, c$ and chlorophyll $d$,in addition to phycoerythrin. This alga belongs to:

Provide the answers for the following analogy-based questions:
$(i)$ Flagellated : Zoospore :: Non-flagellated : ........
$(ii)$ Volvox : Colonial :: Spirogyra : .....

Reproduction in $Spirogyra$ is

Laminarin and mannitol are stored food of $:-$

Sexual reproduction in which cells of two different $Spirogyra$ filaments conjugate is known as