I have been reviewing the basic concepts related to experimental designs, experimental control, and internal and external validity threats. I need assistance with better understanding this scenario to make 2-3 possible conclusions from the results about the relationship between smoking and heart disease symptoms. Is there evidence of main effects and or interactions? Help me understand why or why not. Scenario: Dr. Barnes measured the number of symptoms related to heart disease (range 0 = no symptoms to 20 = many symptoms) in a sample of male and female smokers and non-smokers and got the results shown in table. Table 1. Mean number of heart disease symptoms as a function of partner intimacy and smoking status of participants. Male Female Smoker 8 18 Non-Smoker 5 5