Joey, Jovy and Jojo are solidary debtors under a loan obligation of P$300,000\mathrm{.}00$ which has fallen due. The creditor has, however, condoned Jojo's entire share in the debt. Since Jovy has become insolvent, the creditor makes a demand on Joey to pay the debt.

$1.$ How much, if any, may Joey be compelled to pay?

$2.$ To what extent, if at all, can Jojo be compelled by Joey to contribute to such payment?