I would say Solar Power Engineer.
A pure substance is chemically combined
Therefore a compound is a pure substance because it cant be broken down physically
All elements are pure substances, along with tin, diamond, and etc...
The forces on the mass on the table are balanced because it moves at constant speed. The force to the right is 2mg, the force to the left must also be 2mg. The weight on the left is 1mg so the friction force on the mass on the table is also 1mg to the left.
Answer:
I think the SI unit of A is m^2/s
