Select from options: Continue writing the next sentence.

How to measure length
Choose the most appropriate tool.
There are several tools you can use to measure length, but the right tool will depend on the unit system you plan to use and the size of the length you wish to measure.
Rulers are stiff, straight edges with graduated markings.

Pick your answer from: 1). They are usually made of cast iron and sold in hardware stores. Reference the manual of mechanical tools you plan to use. 2). Typically, one side has markings for inches and the other side has markings for centimeters. These tools are good to use for relatively short lengths. 3). These markings are used on nearly any one unit. Basps are very similar to canes, but the differences are subtle. 4). Many caps use elongated lines when measuring height or weight. Pencils are curved lines coming out of the end of many sticks.
Answer:
2).