Flask a contains photosynthetic green algae in water while flask b contains water with no algae. both are placed under lights set to cycle between 12 hours of light and 12 hours of dark. if the dissolved oxygen concentrations in both flasks are monitored, how will the dissolved oxygen concentration in the flask with algae compare to the control flask?

Researchers are conducting experiments to determine the role of alcohol in the development of depression. after the study is complete, they determine that the relative risk of developing depression is 1.55 with a 95 % ci of 1.2 -1.9. each group is then divided into nonsmokers and smokers. the relative risk for the nonsmokers is 1.12 with a 95% ci of 0.87-1.37. the relative risk for the smokers is 1.7 with a 95 % cl of 1.5-1.9. what type of bias may affect this study? a. procedure bias b. recall bias c. selection bias d. confounding e. lead-time bias