Please solve the following problems using the hardness data from the Jominy end-quench test for 8660 steel and the data for cooling rates at different locations in round bars during several quenches related to positions along a Jominy bar. 1. For a 8660 steel bar with a 2-inch diameter quenched by mildly agitated oil, please estimate the Rockwell hardness for both the surface and the center of the cross section of the bar. 2. A 8660 steel bar was quenched using mildly agitated molten salt. If it is required that the center of the bar should have a Rockwell hardness of at least 45, what is the maximum value for the diameter of the bar?