I think is B sorry if I am worng
Answer
Let t be number of minutes since tap is opened
water is increased by 20 gallons of water per minute.
sugar increase rate of 3 pounds per minute
water :- W(t) = 350 + 10 t
sugar :- S(t) = 10 + 3 t
concentration
C(t) = 
at t = 15 minutes
C(15) = 
C(15) = 
C(15) = 0.11
at beginning t = 0 minutes
C(0) = 
C(0) = 
C(0) = 0.0286
C(15) > C(0)
hence, concentration is increasing as time is passing.
Answer:
(x, y)=(3/4, 3)
Step-by-step explanation:
1 SD away from mean is 68% of data.
2 SD away from mean is 95% of data.
3 SD away from mean is 99.7% of data.
1 SD away:
190+30=220
2 SD away:
220+30=250
This shows we are on the outer 5 percent of the normal distribution.
Since you said "more", that means we only look at the right side of your 5%, which is only 2.5%
answer is D, 2.5%