5 7 17 18 19 Type your answer... 23:47 Time Remaining PAU 5 points When the values of x tend to increase while the values of y tend to decrease; we say that: O there is a negative correlation between the variables. a positive association exists between the two variables. there is a cause-and-effect relationship between the two variables. there is no correlation between the two variables. Return 30% The difference between the weigh of the grass and the weight of fertilizer. Submit 5 points The average time to recover from the flu for healthy adults age 18-24 follows a Normal distribution with mean 5.12 days and standard deviation 0.95 days. If a person in this age group were to recover in 3 days, what is the associated z-score? Give your answer correct to two decimal places. Type your answer... --D - 5 points A horticultural research agency is trying to optimize the growth of the grass in an area for a new project. They are interested in the relationship between the amount of fertilizer used (measured in kg) and the amount of grass grown (measured by weight, in kg). Which of the following is the best choice for the explanatory variable? 1 D