exact object dimensions

how can one determine an objects exact dimensions? i have
imported an OBJ file, selected it and hit ‘N’ to get the “Transform Properties”
dialog. the Size of the object in X, Y and Z dimensions reports as “1.000”
which i know to be entirely incorrect. now i imagine one can scale the object
a percentage with respect to its original size but i would like to give the
object a known dimension. how is this accomplished?

much thanks.

Tab into edit mode and you can set the coordinates of each vertex to exactly what you want with the “n” key.
The “n” key works for verticies as well as objects.