Select the correct text in the passage.
Which sentences indicate that Thomas is dealing with a prototype product?
Thomas got the idea of inventing a low-voltage air conditioner. After several months of trial and error, he developed an AC model blueprint. He finally began his work on its production. With every test, Thomas went on making changes to his new product. Once convinced, he sold the rights of his invention to ABEC Corp for a handsome fee.
Thomas got the idea of inventing a low-voltage air conditioner. After several months of trial and error, he developed an AC model blueprint. He finally began his work on its production. With every test, Thomas went on making changes to his new product. Once convinced, he sold the rights of his invention to ABEC Corp for a handsome fee.