Barry and Mary have accumulated over $$3\mathrm{.}9$ million during their $50$ years of marriage. They have five children and six grandchildren.

a$.$ How much money can they gift to their children in $2020$ without any gift tax liability?

Barry and Mary have accumulated over $$3\mathrm{.}7$ million during their $50$ years of marriage. They have three children and six grandchildren.

B$.$ How much money can Barry and Mary gift to their grandchildren in $2020$ without any gift tax liability?

Barry and Mary have accumulated over $$4\mathrm{.}6$ million during their $50$ years of marriage. They have four children and three grandchildren.

C$.$What is the total amount removed from Barry and Mary's estate in $2020$ if they gift the maximum allowable amount to their children and grandchildren without incurring any gift taxes?