3. MINIMUM NUMBER OF SQUARES AND MOVES

(a) Place the 8 chess pieces on the chessboard so that the minimum number of squares are attacked.

(b) Arrange 8 pieces of one color providing the minimum possible number of moves.

 Solution. Position on figure gives the solution of both problems: (a) only 16 squares are under attack (record was achieved in the last century) and (b) minimal number of moves is only 10 (M. Bezzel , 1848).