You can't know this since the other diameters are not given. It could touch at the .705 dimension ..705 is a basic dimension where the .814 dimension must be in tolerance.
The ball is drawn in by the machinist. There is no assumption or guarantee that it touches the part at the .705 dimension. (it doesn't).
Not fair. You guys are using advanced knowledge of chambers. The .0500 dimension was not given. It was not specified that this was a gauge ball. still good work on solving it! Does this help the OP?