(a) In Cindy Lou Who's multivariable calculus class, the teacher gave a multiple choice quiz with 20 questions. After the quiz, the teacher listed the number of correct answers for each student (x) and the number of incorrect answers (y). The mean number of correct answers in the class was 14.3, with a standard deviation of 2.5, and the mean number of incorrect answers was 6.7, also with a standard deviation of 2.5. The correlation between x and y was. . . -1, -0.5, -0.25, 0, 0.25, 0.5, 1, "can't tell without the actual data"
Choose one and explain your answer briefly.
(b) In a longitudinal study on growth, 1034 children were followed for 15 years. Among other data that the investigators collected were the heights of the children each year. Which of the following two correlations is bigger? Justify your answer briefly.
• r1 The correlation between a child's heights at age 4 and at age 18.
• r2 = The correlation between a child's heights at age 16 and at age 18.

Part a what is the area of triangle i? show your calculation. part b triangles i and ii are congruent (of the same size and shape). what is the total area of triangles i and ii? show your calculation. part c what is the area of rectangle i? show your calculation. part d what is the area of rectangle ii? show your calculation. part e rectangles i and iii have the same size and shape. what is the total area of rectangles i and iii? show your calculation. part f what is the total area of all the rectangles? show your calculation. part g what areas do you need to know to find the surface area of the prism? part h what is the surface area of the prism? show your calculation. part i read this statement: “if you multiply the area of one rectangle in the figure by 3, you’ll get the total area of the rectangles.” is this statement true or false? why? part j read this statement: “if you multiply the area of one triangle in the figure by 2, you’ll get the total area of the triangles.” is this statement true or false? why?

There were 816 people at a concert when a band started to play. after each song, only half the people stayed to hear the next song. how many people were left at the concert after x songs? write a function to represent this scenario.

Jonah runs 3/5 miles on sunday and 7/10 mile on monday. he uses the model to find that he can ran a total of 1 mile . what mistake does jonah make