What is a question about this article? If the question is unanswerable, say "unanswerable".

The City of Charleston Fire Department consists over 300 full-time firefighters. These firefighters operate out of 19 companies located throughout the city: 16 engine companies, two tower companies, and one ladder company. Training, Fire Marshall, Operations, and Administration are the divisions of the department. The department operates on a 24/48 schedule and had a Class 1 ISO rating until late 2008, when ISO officially lowered it to Class 3. Russell (Rusty) Thomas served as Fire Chief until June 2008, and was succeeded by Chief Thomas Carr in November 2008.

How many tower companies doesn't the fire department have?
unanswerable