Firstly, using the topographic map, you need to complete a topographic profile of the mount todd region. this topographic profile should have no vertical exaggeration (i. e. ve = 1). the profile/ cross section should be between coordinates: a and b as i have marked on the second map. once you have completed the topographic profile, you need to use the information contained on the geological map and the key that you have constructed to add geological detail onto the topographic profile to produce a geological cross section.