So you find 8% of 1000 and that would be 80 and add 80 to 1000 because she gained 80 dollars in interest over 48 months so in 48 months she has $1080 dollars.
70 miles per hour 5280 feet per mile 5280 x 70 = 369600 feet per hour 3600 seconds per hour 369600 divided by 3600 = 102.67 feet per second (rounded to the nearest hundredth)
