Classify the following graph as a cross-sectional study or a time-series study. Temperature in Temperature () 10 20 30 40 50 60 70 Days at Temperature 0 2 4 6 8 10 The horizontal axis is labeled Temperature () and is divided into 7 categories which are labeled as follows: 10, 20, 30, 40, 50, 60, 70. The vertical axis is labeled Days at Temperature and is divided into 5 equally sized classes, with tick marks given at the start and end of each class which are labeled as follows: 0, 2, 4, 6, 8, 10. The bar graph displays the following data: 10 has a height of 2, 20 has a height of 3, 30 has a height of 4, 40 has a height of 5, 50 has a height of 6, 60 has a height of 7, 70 has a height of 8