Medical researchers studying a medication in male and female patients 20 to 29 years old noticed that, up to a certain amount, a larger concentration of an active ingredient lead to greater levels of symptom relief. What is the explanatory variable?

A) age of patient
B) gender of patient
C) amount of symptom relief
D) concentration of active ingredient

34 cup. a serving of vegetable soup is 23 cup. the restaurant sold 20 servings of chicken noodle soup and 18 servings of vegetable soup. how many more cups of chicken noodle soup did they sell than cups of vegetable soup?

This stem-and-leaf plot represents the heights of the students on ralph's basketball team. one student's height is missing from the plot. if the mean height of all the students on the team is 61 inches, what is the missing height? a. 55 in. b. 59 in. c. 61 in. d. 65 in.

Ascientist studied a population of workers to determine whether verbal praise and/or tangible rewards affect employee productivity. in the study, some workers were offered verbal praise, some were offered tangible rewards (gift cards, presents, and some were offered neither. the productivity of each participant was measured throughout the study by recording the number of daily tasks completed by each employee. which inference might the scientists make based on the given information? a.) the number of daily tasks completed by each employee may influence the dependent variable, which is whether the employee receives verbal praise, tangible rewards, or neither. b.) verbal praise and/or tangible rewards may influence the independent variable, which is the number of daily tasks completed by each employee. c.) verbal praise and/or tangible rewards may influence the dependent variable, which is the number of daily tasks completed by each employee. d.) the dependent variables, which are verbal praise and tangible rewards, may influence the number of daily tasks completed by each employee.