In a research study, students were randomly assigned to three different groups. Group 1 drank no cups of coffee, group 2 consumed 1 cup of coffee, and group 3 consumed 2 cups of coffee. Following this, all the participants took an IQ test. What is the independent variable

Look at the figure below: triangle abc is a right triangle with angle abc equal to 90 degrees. the length of ac is 5 units and the length of ab is 4 units. d is a point above c. triangle adc is a right triangle with angle dac equal to 90 degrees and dc parallel to ab. what is the length, in units, of segment cd?