PLS HELP☆☆ If correct will give BRAINLIEST and give extra points when answered with correct answer!! thank you ​

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.

Arectangle has a width of 9 units and length of 40 units. what is the length of a diognal. a. 31 unitsb. 39 unitsc. 41 units d. 49 units

1. the wheeling bridge in west virginia is about 307 meters long. if you walk with a stride of about meter, about how many steps would it take you to cross this suspension bridge?