It takes alex 22 minutes to walk from his home to the store. the function f(x)=2.5x models distance that alex has walked in x minutes after leaving his house to go to the store. what is the most appropriate domain of the function
a : 0 ≤ x ≤ 55
b : 0 ≤ x ≤ 22
c : 0 ≤ x ≤ 8.8
d : 0 ≤ x ≤ 2.5