1. The rst step in selecting a statistical methodology or a graphing technique is to identify your variables and the roles that reach variable plays in your analysis, and to classify each variable by its information type. You identified the variables and roles for scenarios a-d in Homework 1. Now, please classify each variable according to a specic type (continuous, discrete, nominal, or ordinal], and briey explain the reasons for your classifications. a. [1 point] Deposits of a protein known as amyloid :9 [A B ) in the brain are closely associated with Alzheimer's disease, but can only be observed in an autopsy. This means that they cannot be used to diagnose Alzheimer's in living patients. Hoping to develop a diagnostic test that would allow earlier treatment of the disease, DeMattos et al. [2ll2, Science 295:2264226?) injected 49 mice with a monoclonal antibody which causes A B that is present in the brian to be released into the blood, where it can be detected. Then they compared the amount of A B that accumulated in the blood over a 24-hour period after injection to the A B load in the mouse's brain. *Brain A level: *Blood A level: Reasoning