The trustees of a college have accepted a gift of $$$$425000,$ but are required to deposit it in an account paying $10\%$ per$$ year, compounded semiannually. They may make equal withdrawals at the end of each$$ six$-$month period, but the money must last $5$ years.

a$.$ Find the amount of each withdrawal.

b$.$ Find the amount of each withdrawal if the money must last $8$ years.

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