Which property is (3+5) times 6 = 3 + (5 times 6)

Hey free points ! people i have a few math questions on my profile consider looking at them i have to get done in 30 mins!

1.multiply and simplify if possible. √7x (√x − 7√7) 2. what is the simplest form of the radical expression? 33√2a−63√2a

Atreasure chest sinks at a rate no less than 20 feet er second. the floor of the icean is at most at -4,200 feet. will the tresure chest reach the ocean floor in less than 3 minutes? explain.