Amazon tests a $9.99/month grocery subscription service for Prime members, offering unlimited Whole Foods and Amazon Fresh grocery delivery on orders over $35 (Annie Palmer/CNBC)

Annie Palmer / CNBC:

Amazon tests a $9.99/month grocery subscription service for Prime members, offering unlimited Whole Foods and Amazon Fresh grocery delivery on orders over $35  —  – Amazon is betting members of its Prime program will want to pay a separate monthly fee for unlimited grocery delivery on some orders.