From the choices provided, the better answer is ' T ' .
Borax, also known as sodium borate, sodium tetraborate,
or disodium tetraborate, is an important boron compound,
a mineral, and a salt of boric acid. Powdered borax is white,
consisting of soft colorless crystals that dissolve easily in water.
Its molecular (chemical) formula is <span>
<span>Na₂B₄O₇·10H₂O or Na₂[B₄O₅(OH)₄]·8H₂O .</span></span>
Answer:
Efficiency of a machine is how well the machine works and what the machine is capable of doing.
Mechanical advantage=Load/Effort.
720/180=4