Compute the maturity value as indicated for each of the following notes receivable.

A $$9,000,6\%,3-$month note dated July $20.$

Determine the interest on the following notes:

$($B$)$$$800,6\%,5$ month

$($a$)$ $$5,000$ at $6\%$ for $90$ days

$($C$)$$$6,000$ at $8\%$ for $60$ days

$($D$)$ $$1,600$at $7\%$for $6$ months