Final answer:
The PT can supervise 2 aids providing patient care.
Step-by-step explanation:
To determine how many aids the PT can supervise, we need to compare the number of PTAs and aids. The question states that the PT has 2 PTAs and 4 aids. Since the PTAs are assistants to the PT, we can assume that the PT can supervise both PTAs.
Now, for the aids, we need to check the ratio of PTAs to aids. The PT has 2 PTAs, so they can supervise 2 aids, leaving us with 2 remaining aids. Therefore, the PT can supervise a total of 2 aids providing patient care.