Problem
Mia practices her flute for 30 minutes each evening. This can be represented by the equation \( t=30 \mathrm{~d} \). What is the independent variable in the equation above? A. 30 minutes B. the number of days C. total pinutes practiced D. total number of days
Solution
Step 1 ：Identify the given equation: \(t = 30d\).
Step 2 ：Recognize that the dependent variable is \(t\) and the independent variable is \(d\).
Step 3 ：Identify the correct option as B. the number of days.
