From this question I take it that you need to know what is 130% of 45 mg. 130% of 45 is equal to 1.3x45, which is 58.3. So, your answer is 58.3 mg of the vitamin.
The one the points down shows a negative correlation. a positive correlation points up
your answer here is d
Okay so 6.25 a student then it goes to 4.50 for 15 more students at 70 students its 358.75 now it drops another 1.75 so it would be 368.75 for 80 students so the equation is 4.48 x 80 = 368.75. enjoy :D