When using the Measure Item tool, your cursor will change depending on what item you have pre-selected (hovering over). The results of your measurements will be different, based on the items you select.
Point
o Coordinate Values
Line
o Length
o Start Point (Point 1)
o End Point (Point 2)
o Direction Vector
Curve
o Length
o Start Point (Point 1)
o End Point (Point 2)
Arc
o Length
o Angle
o Radius
o Diameter
o Start Point (Point 1)
o End Point (Point 2)
o Center Point
Surface
o Surface Area
o Center of Graivty
o Perimieter
Cylindrical Surface
o Area
o Radius
o Center of Gravity
o Perimeter
Planar Surface
o Surface Area
o Plane Equation
o Center of Gravity
o Perimeter
Conic Surface
o Surface Area
o Center of Gravity
o Perimeter
Spherical Surface
o Radius
o Surface Area
o Center of Gravity
o Perimeter
Volume
o Volume
o Surface Area
o Center of Gravity
The display of these results can be toggled on or off by clicking Customize… in the Measure Item dialog box.