What five letter word that is to find an approximate value for a number? it starts with an i really don't understand

You are measuring the dimensions of the floor in your bedroom because you are planning to buy new carpet. which unit of measure is the most appropriate to use in this situation?

The sales tax rate is 7.25%. how much tax in dollars is added on an item that costs $56.00? a. $4.06 b. $7.25 c. $14.50 d. $60.06

10 ! a train starts from grand city and travels toward belleville 388 miles away. at the same time, a train starts from belleville and runs at the rate of 47 miles per hour toward grand city. they pass each other 4 hours later. find the rate of the train from grand city.