Which two of the following are MAIN ideas from the article? A) Bakeries began delivering bread to supermarkets, saving women time and stress. B) Frank Conrad's radio station was located above his garage near Pittsburgh. C) The radio made it easier for companies to advertise products to large numbers of people. D) Buying goods on credit made it possible for Americans to own more than ever before.

From the question, C and D is the answer

Explanation:

Business sales grew during the 1800-1900s, due to two following reasons which included advertising public at large which says that a greater brand recognition would familiarize the people with the product as a result increased sales would be witnessed, also allowing customers access to credits so that they would buy more from them .

The growth of business today, is more of thought dependent, but in the earlier times technological advances was not common as compared to now, so radio   dependence was mainly used for the advertising of products at large scale, and for customer retention businesses were used to allow certain level of credit to each customer.

i am pretty sure it is d.

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