How can you use models to explain why 3.1 = 3.10

Will give brainliest! aubrey was offered a job that paid a salary of $45,000 in its first year. the salary was set to increase by 2% per year every year. if aubrey worked at the job for 20 years, what was the total amount of money earned over the 20 years, to the nearest whole number?

At a sale this week, a desk is being sold for $213. this is a 29% discount from the original price. what is the original price?

Need on this geometry question. explain how you did it.