Help i will give brainliest

Step-by-step explanation:

Area of circle = 56 cm²

                   πr² = 56

                 3.14r² = 56

                         r²=56/3.14

                        r²= 17.83

                        r = √17.83

                        r = 4.22 cm

The diameter of the circle  = diagonal of the square

Diagonal of the square = 2 * 4.22 = 8.44 cm

x² + x² = 8.44²

2x² = 71.2336

  x² = 71.2336/2

  x² = 35.6168

x = 5.967 cm

reduce the friction between its moving parts

step-by-step explanation:

in fact, by reducing the friction between the moving parts of the machine, it is possible to reduce the energy wasted due to this friction; therefore, more input energy is converted into useful work, and this will improve the efficiency of the machine.