Do the following operations without a calculator. Be sure to express answers in scientific notation. You may round your answers to one decima a. (3x103) x (2x109) b. (5x106) + (9x105) c. (410) + (2x10) C. a. (3x103) x (2x10) = 6x10 (Use the multiplication symbol in the math palette as needed.) b. (5x106) + (9x105) = (Use the multiplication symbol in the math palette as needed.) C. (4x109)+(2103) =]]]]