Consider the following two groups of words:

Group 1 Group 2

AREA...................ERST

FORT...................FOOT

HOPE...................HEAT

SPAR...................PAST

THAT...................PROF

TREE...................STOP

All the words in groups 1 and 2 can be formed from the nine letters A, E, F, H, 0, P, R, S, and T. Develop a model to assign a unique numeric value from 1 through 9 to these letters such that the difference between the total scores of the two groups will be as small as possible.