Examine this scenario and answer the following question(s):

Bobbie Black died unexpectedly and had executed a will. Bobbie was a single woman with no children. She left $20,000 each to her dear friends, Sally and Mona. She also left $20,000 to the local no-kill animal shelter to provide for the care of her dog, Lucky. The remainder of her property was left to her ex-husband, Paul (whom she made a beneficiary specifically after they were divorced). Assume Bobbie had a $6 million estate.

Bobbie's will has the following clause:

I direct that my Executor pay out of my residuary estate, without apportionment, all estate, in- heritance, succession, and other taxes (together with any penalty thereon), assessed by reason of my death, imposed by the Government of the United States, or any state or territory thereof, or by any foreign government or political subdivision thereof, in respect to all property required to be included in my gross estate for estate or like death tax purposes by any of such governments, whether the property passes under this will or otherwise, including property over which I have a power of appointment, without contribution by any recipient of any such property.

Who will bear the tax burden of Bobbie's estate?