I need help solving for x with angles

Bob the builder is making 480kg of cement mix. this is made by cement, sand and gravel in the ratio 1: 3: 4

Which of these would have been most likely to have been a carpetbagger during the reconstruction era? a) a new york businessman who relocated to mississippi b) a former slave who was able to buy land in birmingham c) a carolina-born politician who supported the democratic d) a former confederate officer who owned a farm in memphis eliminate

Stu and ambrose are working together on a study of whether diet is related to students' mental health. first, they randomly select 10 students from the student center and 10 students from the office of counseling and psychological services. then, they ask students to rate their diet in terms of healthiness on a scale of 1-100 before completing a 20-item mental health survey. a) name one of the constructs being studied b) how was the construct you named above operationally defined in this experiment? e) was the variable you described above their independent variable, their dependent variable, or a controlled variable? d) what is a confounding variable? what is a potential confound in this study?