$4.)$ You are using two city control points that are referenced to state plane grid for a survey. You know from a control data sheet that the grid distance between these points is $2319\mathrm{.}28ft.,$ the sea level factor $($elev$.$ factor$)$ is $0\mathrm{.}99998291,$ and the scale factor is $0\mathrm{.}99994632.$

a$)$ Combined factor

b$)$ datum adjustment factor

c$)$ ground distance to expect to measure between the two points