triangles are equal.So add 0.75 three times and write the answer as I mentioned. Also you must do it according to the book.I mean like,you adds it 3 times because triangle is 3 sided and it's a equilateral triangle.
Positive correlation means that if x goes up then y goes up, negative correlation means that if x goes up then y goes down. Since both x and y are increasing each time, it is positive.
