Class was a little different today. You have to be able to use your imagination to figure out some referents for which you can base your estimations.
Now that we are onto Area dont forget that Area = length x width (A = l x w)
As an application of these principles, check out:
Things are pretty high tech nowadays, but if you went back even 50 years and asked a forester how he measured the proposed cut block, he would have likely given you an answer based on his strides. Ie: 1200 strides by 4500 strides, which correlates to about 1200 yds by 4500 yds or 5,400,000 yds square. From this, he could esitmate the value of timber on that land and give his recommmendation to the loggers that would apply for the wood rights of that land.
Interesting stuff eh!