A small block with mass $0\mathrm{.}0375$ kg slides in a vertical circle of radius $0\mathrm{.}525$ m on the inside of a circular track. During one of the revolutions of the block, when the block is at the bottom of its path, point A$,$ the magnitude of the normal force exerted on the block by the track has magnitude $4\mathrm{.}00$ N $.$ In this same revolution, when the block reaches the top of its path, point B$,$ the magnitude of the normal force exerted on the block has magnitude $0\mathrm{.}690$ N

How much work was done on the block by friction during the motion of the block from point A to point B $?$