Penelope wants to buy two necklaces, one for his sister and one for herself. The necklace for her sister cost $42.00, and the necklace for herself costs $28.00. The sales tax on the purchases is 8%. Find the total cost of Peter's purchases, including the sales tax. If necessary, round your answer to the nearest cent. Show Work!

(A) $64.40
(B) $5.60
(C) $75.60
(D) $70.00