Q1: What is the difference between quiescence and dormancy?

Quiescence is a state of suspended growth of the embryo, or a resting condition of the seed. It involves factors in the seed itself which put it into a resting state (such as dessication). Quiescent embryos will resume growth at any time upon exposure to favorable conditions (water, oxygen and warmth).

Dormancy is a state that requires a special event or "trigger" before the embryo can resume growth, such as fire, scarification or cold treatment. Until such an event occurs, the seed is prevented from germinating.

Fast Plants seed is quiescent but not dormant. It does not require a special event to resume development and growth. Many wild brassicas have dormant seed, whose dormancy can be broken by treatment with gibberellin an other plant growth hormones..