So i know everybody says that they need help asap and stuff, and tbh i have until umm 11:59 to turn this in so if u get to this later thats cool too. thx guys : Sally Smith is a chemist with XYZ Pharmaceutical. She mixes a 9% solution of sulfuric acid with a 30% solution of sulfuric acid to produce an 18% solution. How much 9% solution and how much 30% solution will be needed to make 21L of 18% solution?

4860 % mby idk this stuff

4a. is 3 miles every hour

4b. is 1/3 of an hour per mile

step-by-step explanation:

d. 24+-0.114

step-by-step explanation:

the question requires us to calculate the approximate 95% confidence interval for the mean number of ounces of ketchup per bottle in the sample given the following statistics;

sample mean = 24

standard deviation, σ = 0.4

sample size , n = 49

the confidence interval for a population mean is calculated using the formula;

sample mean ± z-score*(σ/sqrt(n))

the z-score associated with a 95% confidence interval, from the standard normal tables, is;

1.96

substituting these values into the formula;

24 ± 1.96*(0.4/7)

= 24 ± 0.112

from the alternatives given, choice d is closest to the above expression;