A tape measure, or a measuring pole.
To find the relationship in width and area you can use the formula area/length = width. To find the area of a room you multiple the length by the width.
To find the volume of a box, you would use the formula Volume = Length x Width x Height. Measure the length, width, and height of the box in units (such as centimeters or inches), then multiply these values to calculate the volume of the box.
you need length and width length multiply width = area length + length + width + width = perimeter
millimetres
Use a ruler, to find out the area do width times length.
You would use meters.
scale
A balance or scales.
centimeters
leanth times width
meter