A $2-$kg block is placed on a plane inclined at an angle of $30$ to the horizontal and is counected to a spring fastened ae the try of the plane. The spring is parallel to the incline and has a ferce constant of $100\frac{N}{m}.$ The block is released from rest when the spriag las its equilibriom lezgth. If the block moves a distance of $10$ cm befoer coraing to an instantanoous rest, find the magnitude of the force of friction betw oen the block and the plate.