12.) During the first 3 weeks of training, a runner runs 20 miles, 22 miles, and 21 miles. How many miles must she run during the fourth week to have a mean of at least 22 miles per week?
10 miles
15 miles
20 miles
25 miles

Describe in detail how you would construct a 95% confidence interval for a set of 30 data points whose mean is 20 and population standard deviation is 3. be sure to show that you know the formula and how to plug into it. also, clearly state the margin of error.

Can someone show me step by step how to do this?

Asalsa recipe uses green pepper, onion, and tomato in the extended ratio 3: 5: 7. how many cups of tomato are needed to make 105 cups of salsa? a. 7 b. 21 c. 35 d. 49