Constructing BST in Figure 1.
[3 (size=1, height=0)]
[7 (size=4, height=2)]
[9 (size=1, height=0)]
[11 (size=2, height=1)]
[14 (size=8, height=3)]
[15 (size=2, height=1)]
[17 (size=1, height=0)]
[20 (size=3, height=2)]
[22 (size=13, height=4)]
[24 (size=1, height=0)]
[26 (size=2, height=1)]
[30 (size=4, height=2)]
[37 (size=1, height=0)]
[41 (size=22, height=5)]
[50 (size=1, height=0)]
[54 (size=3, height=1)]
[59 (size=1, height=0)]
[60 (size=4, height=2)]
[64 (size=8, height=3)]
[71 (size=2, height=1)]
[75 (size=1, height=0)]
[79 (size=3, height=2)]

Yes, t contains 24
No, t does not contain 19

Testing span() method:
Yes, there are 9 items between 22 and 59 (inclusive).
Yes, there are 6 items between 17 and 36 (inclusive).
Yes, there are 6 items between 13 and 25 (inclusive).
Yes, there are 4 items between 22 and 35 (inclusive).
Yes, there are 8 items between 5 and 22 (inclusive).

Adding 12 should trigger a rebalance...

Output looks like Figure 4 *PLUS* node 12: 
[3 (size=2, height=1)]
[7 (size=1, height=0)]
[9 (size=7, height=3)]
[11 (size=2, height=1)]
[12 (size=1, height=0)]
[14 (size=4, height=2)]
[15 (size=1, height=0)]
[17 (size=14, height=4)]
[20 (size=2, height=1)]
[22 (size=1, height=0)]
[24 (size=6, height=2)]
[26 (size=1, height=0)]
[30 (size=3, height=1)]
[37 (size=1, height=0)]
[41 (size=23, height=5)]
[50 (size=1, height=0)]
[54 (size=3, height=1)]
[59 (size=1, height=0)]
[60 (size=4, height=2)]
[64 (size=8, height=3)]
[71 (size=2, height=1)]
[75 (size=1, height=0)]
[79 (size=3, height=2)]


Removing 41... 
Yes, 41 was removed

BST after removing 41 (50 should be new root): 
[3 (size=2, height=1)]
[7 (size=1, height=0)]
[9 (size=7, height=3)]
[11 (size=2, height=1)]
[12 (size=1, height=0)]
[14 (size=4, height=2)]
[15 (size=1, height=0)]
[17 (size=14, height=4)]
[20 (size=2, height=1)]
[22 (size=1, height=0)]
[24 (size=6, height=2)]
[26 (size=1, height=0)]
[30 (size=3, height=1)]
[37 (size=1, height=0)]
[50 (size=22, height=5)]
[54 (size=2, height=1)]
[59 (size=1, height=0)]
[60 (size=3, height=2)]
[64 (size=7, height=3)]
[71 (size=2, height=1)]
[75 (size=1, height=0)]
[79 (size=3, height=2)]


Removing 50 should trigger a rebalance 
Yes, 50 was removed
[3 (size=1, height=0)]
[7 (size=4, height=2)]
[9 (size=2, height=1)]
[11 (size=1, height=0)]
[12 (size=10, height=3)]
[14 (size=2, height=1)]
[15 (size=1, height=0)]
[17 (size=5, height=2)]
[20 (size=2, height=1)]
[22 (size=1, height=0)]
[24 (size=21, height=4)]
[26 (size=2, height=1)]
[30 (size=1, height=0)]
[37 (size=4, height=2)]
[54 (size=1, height=0)]
[59 (size=10, height=3)]
[60 (size=2, height=1)]
[64 (size=1, height=0)]
[71 (size=5, height=2)]
[75 (size=2, height=1)]
[79 (size=1, height=0)]