a) the markdown is $9.99
b) original sale price is $39.99
c) after using the coupon the price would be $29.99
in order to find this out you would first divide the original price of 39.99 by 100 in order to find out what 1% is. Then you would multiply this number by 25 to find out what 25% is. Then you would subtract the original amount of 39.99 by the 25% amount in order to find out how much is taken off