(1.8•10^1)(7•10^5) looking for answer

The fence around a quadrilateral-shaped pasture is 3a^2+15a+9 long. three sides of the fence have the following lengths: 5a, 10a-2, a^2-7. what is the length of the fourth side of the fence?

On average a herd of elephants travels 10 miles in 12 hours you can use that information to answer different questions drag each expression to show which is answers

Change negative exponents to positive. then solve. round to four decimal places