GRO2 and GRO4 are image extensions associated with a series of graphing calculators released by Hewlett-Packard, called the HP-49G series. Features delivered by these devices included solving advanced algebra equations and plotting graphs. GRO2 files most likely contain screen shots or commands associated with HP-49G calculators.
The quick and simple way to handle your files is to get a quality piece of software, such as reaConverter. This software is extremely efficient in managing a wide range of batch conversions. As you will soon realize, reaConverter will help you avoid spending countless hours trying to figure out how to convert multiple GRO2 files as once.
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