Judging by appearance, name an acute angle, an obtuse angle, and a right angle

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.

Two streets intersect at a 30- degree angle. at the intersection, the are four crosswalks formed that are the same length. what type of quadrilateral is formed by the crosswalks?

Which of these sequences is a geometric sequence a 1,2,4, 7, 11, 16, 22. b. 2.4.8.14.22.38 c.3.6.9. 15.18,21 d. 3,9,27,81,243,729,