ZFP - US distance measurement unit change to same as CWeb

ZFP user complained about US studies measurement units.

There were used CWeb, and then they replaced it to ZFP.

When they use distance tool on the viewport of graph area, the unit was shown as speed(cm/sec) and time(sec) on CWeb.

But ZFP shows those ones as pixels.

They requested to add the same function to ZFP.

Please refer the attached capture files.