How many weights of $100$ gram are required in weighing scale to weigh $400$ gram goods?

For making weighing equal, give the weight in given box:

Write 'H' below the heavier pan and 'L' below the lighter pan.

For making weighing equal, give the weight in given box:

For making weighing equal, write the weight in other side

A triangle weighs the same as a circle. Balance the above scale.
How many triangles do you need?

Give the standard unit to measure.

Write 'H' below the heavier pan and 'L' below the lighter pan.

For making weighing equal, give the weight in given box:

Standard unit of measuring weight _____(kilogram/metre)