6.02 ionic and covalent bonds. i want to do the first option, and i am just very confused on what to do. i need ! can someone figure out how to do this for me?

Scientists often have to deal with numbers that are either very large or very small. for example, the radius of the sun is approximately 696,000 kilometers, while bacterial cells are as small as 1.9 × 10-4 millimeters. express each number in an alternate form.