On an inclined plane with an angle at the base of 60 ° there is a board of mass M, and on the board is a block of mass m = 2.3 kg. The bar and the board are interconnected by means of a weightless inextensible thread, thrown over a weightless block. Coefficients of friction between the surfaces of the bar and the board 0.2; boards and planes 0.4. At what values of the board mass M will the bar move downward?

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