Plz someone i am desperate. plx answer my other math question too plz

What is the probability of drawing three queens from a standard deck of cards, given that the first card drawn was a queen? assume that the cards are not replaced.

Select all of the quadrants that the parabola whose equation is y=√x-4 (principal square root) occupies. i ii iii iv

Awater holding tank measures 105 m long, 50 m wide, and 8 m deep. traces of mercury have been found in the tank, with a concen- tration of 60 mg/l. what is the total mass of mercury in the tank? answer in units of kg.