Mandy and Hal (mother and son) purchased land for $600,000 as joint tenants with right of survivorship. Of the $600,000 purchase price, Mandy provided $300,000 and Hal $300,000 (of which $200,000 had been received as a gift from Mandy). Hal dies first when the land is worth $3,000,000. As to the land, Hal's gross estate must include: a. $2,500,000. b. $1,500,000 c. $3,000,000 d. $500,000