What is the purpose of the expressions (1) and (2) presented in the last paragraph? The expressions (1) and (2) are used to calculate the necessar...

What is the purpose of the expressions (1) and (2) presented in the last paragraph?

The expressions (1) and (2) are used to calculate the necessary time for each pass in the machining process.
The expressions (1) and (2) are used to calculate the total depth to be removed and the number of passes necessary to achieve it.
The expressions (1) and (2) are used to calculate the cutting force in the machining process.