The regular prices of sandals at a shoe store are marked down by 15%. look at each sale price and determine whether it is a 15% markdown to the nearest cent. select yes or no. a. regular price: $24.30; sale price: $20.66 yes no b. regular price: $55.80; sale price: $40.80 yes no c. regular price: $66.50; sale price: $56.53 yes no