Nikkie and Jean have two children, Richard (age 4) and Roberta (age 3). For purposes of the tax on a child's unearned income, Richard has net unearned income of $6,000 and Roberta has net unearned income of $4,000. Assuming that their total tax on a child's unearned income for 2016 is $2,400, allocate the total parental tax to Richard and Roberta.
a. Richard's parental tax $____________
b. Roberta's parental tax $____________