Also, for number 1. This is how far I got.
Using the properties of a median through a centroid, I found OB through pythagorean theorem
I also found AO through median properties
Notice that AOB is a right angle through supplements.
I you used pythagorean theorem to find AB?
Notice triangles AOB and ZOB are similar.
Since it is a median, we know that the triangles ZOB and AOB are in a ratio of 1:2, respectively. I also know the area of AOB because base and height are known.
So, how would I find OZ?