Hops are the flower clusters of a plant, Humulus lupulus, used in brewing beer. Hops with a higher -acid content provide more biOerness and acid content is used to measure hops quality. A study examined how climate change is affec,ng acid content in hops. Temperature records and hops produc,on in the Czech Republic between 1954 and 2006 were examined. From each year, average summer temperature and the average annual percent -acid content of many hops plants was available.

1. What are the individuals in this study? Remember, the individuals are the objects or en,,es which are being measured by both variables. A. The hops plants B. The Czech Republic C. The temperatures D. The years

2. What is the explanatory variable in this study? A. The number of hops plants measured each year B. The temperature, because we think changes in temperature causes changes in acid content C. The acid content, because we think acid content causes changes in temperature D. There is no explanatory variable

3. What is the response variable in this study? A. The number of hops plants B. The temperatures C. The average acid content in hops plants D. There are two response variables because it is a correlation problem

4. Which summary calculation would best answer the question as stated? A. Two means B. A time plot C. Correlation D. Linear regression