About half. It is considered an active super-volcano.
No. Most of Yellowstone lies outside of the Yellowstone Caldera, though this caldera still takes up a large portion of the park. A larger portion of the park is in the older Island Park Caldera, which partly overlaps the Yellowstone Caldera. This still takes up a minority of the park.
No. For one thing, the Yellowstone volcano is not a mountain, it is a caldera. It is usually referred to as the Yellowstone caldera or the Yellowstone supervolcano.
The Yellowstone caldera.
The Yellowstone caldera is associated with a hot spot, not a plate boundary.
An eruption of the Yellowstone caldera occurs it will likely be an extinction level event.
The Yellowstone Caldera, also known as the Yellowstone Supervolcano, is a volcanic caldera and supervolcano estimated to be an area of about 34 X 45 miles (55 X 72 km).
Yellowstone Caldera, Wyoming, USA
There is the Yellowstine Caldera in Yellowstone, Wyoming.
No. Most of Yellowstone is outside of the caldera.
Yellowstone Caldera
The Yellowstone caldera is not "overdue" for an eruption. You may have heard that the Yellowstone Caldera erupts regularly every 600,000 years and the last major eruption was 640,000 years ago. In reality the caldera does not erupt regularly and as gone as long as 800,000 years without a major eruption.
Yellowstone Caldera, Yellowstone National Park, USA