On June 1, 2023, merchandise subject to terms 2/10: N/30 was sold on account to a customer for $23,500. On June 3, 2023 the seller issued a credit memorandum for $5,100, accepting merchandise returned by the customer. This was prior to payment by the customer. [10 points ea. 20 point total] a) What amount of cash will be collected by the seller if the payment is made by the customer on June 8, 2023? b) What is the amount of cash collected by the seller if payment is made by the customer on June 21, 2023?