Subjecting the growing of which plant to a cold treatment stimulates subsequent photoperiodic flowering response?

$A$ short-day plant was exposed to alternating red-far red light treatments. What would happen if the last treatment was of far-red light?

Write a short note on: $(1)$ Vernalisation.

Photoperiodism was first characterised in

Assertion: Dark period plays a more important part in flowering than the light period.
Reason: Flowering occurs in short-day plants if the dark period is interrupted by a light break.

Florigen results in the conversion of