A rigid disk of radius \(R\) rotates in a vertical plane about a fixed horizontal axle through its center. At the instant shown, a point \(P\) on the outer rim of the disk is at the highest position directly above the axle, moving to the right with instantaneous speed \(v\) and angular speed \(\omega\). The disk is slowing down with a constant angular deceleration of magnitude \(\alpha\). Which of the following correctly identifies the direction of the total linear acceleration vector \(\vec{a}\) of point \(P\) at this instant and gives the correct expression for \(\tan\phi\), where \(\phi\) is the angle of \(\vec{a}\) measured from the inward radial line toward the axle?