Standard Appliances obtains refrigerators for $$1,560$ less $28\%$ and $5\%.$ Standard's overhead is $17\%$ of the selling price of $$1,610.$ A scratched demonstrator unit from their floor display was cleared out for $$1,240.$

a$.$ What is the regular rate of markup on cost for a demonstrator unit?

$\%$

Round to two decimal places

b$.$ What is the rate of markdown on the demonstrator unit?

$\%$

Round to two decimal places