Under Rowena's will, Mandy $($Rowena$\text{'}$s sister$)$ inherits her property. One year later, Mandy dies.

Based on the following independent assumptions, what is Mandy's credit for the tax on prior transfers?

Click to access Exhibit $18\mathrm{.}2,$ Credit for Tax on Prior Transfers $.$

a$.$ The estate tax attributable to the inclusion of the property in Rowena's gross estate is $$700,000,$ and the estate tax attributable to the

inclusion of the property in Mandy's gross estate is $$800,000.$

Mandy's credit for the tax on prior transfers is $

b$.$ The estate tax attributable to the inclusion of the property in Rowena's gross estate is $$1,200,000,$ and the estate tax attributable to the

inclusion of the property in Mandy's gross estate is $$1,100,000.$

Mandy's credit for the tax on prior transfers is $

c$.$ How do your answers to the above questions change if Mandy died seven years after Rowena?

The tax credit percentage used would be

$\%.$