Some advance questions about items

Great game guys. I've got questions about items since from descriptions it's not always clear how they work:

1. Hush and Sword Breaker. For how long those items apply their debuff?
2. Ionic spark (enemy takes 200 magic damage whenever they cast their ability). Does the effect of item global? Like front tank will be shooting sparks at an enemy assassin who jumped far away into a back lane?
3. RapidfireCannon(basic attack cannot miss) VS PhantomDancer(dodge all critical strikes). So if basic attack crits. Which item will win?
4. Luden's Echo(Special ability deal 200 magic damage to all adjacent enemies). Let's say Brand has this item. Will its effect apply on every bounce?
5. Morellonomicon (Special Ability deal 2.5% of target maximum health true damage per second). How many seconds we are talking about? Until the end of a round?
6. Yuumi (becomes a sorcerer). Sorcerer's passive is basic attacks restore twice as much manna. If Yummu put on Lucian who by the way needs only 50 mana to cast his ability. And when he casts it he attacks twice. Will Yummi procs two times on his ability?
7. Rageblade (gain 3% attack speed on-hit). If a champion has two of them will he be granted 6% attack speed on-hit?