Can I work while I am on a business visit in the United States?

No. A business visit means you are doing business in the United States. Doing business entails such things as attending meetings, signing contracts, taking part in seminars, obtaining purchase orders for your products, visiting institutions and the like. What you cannot do is "hands-on" work such as answering phones, typing letters, making sales calls for a US company and the like. There is a fine line between these two activities that you must not cross.