Sixth Form homework question: American monument of Islay

This is the American monument on a lonely rocky headland on the island of Islay. It commemorates lives lost on two ships that were wrecked in sight of the point during the First World War. Such a remote and prominent point makes it far more likely to be hit by lightning because the shorter distance between it and the clouds means that the electric field strength above it is bigger than in surrounding places. When the electric field strength reaches a critical value, air will conduct. To deter lightning, there is a lightning conductor up the side.Your job is to look at the photographs to estimate some dimensions, look up one important number on the Internet and then to calculate the resistance of the lightning conductor.