Answer
See the detailed answer below.
Work Step by Step
a) See the figures below, and recall that: $F_n\rightarrow$ Normal force. $F_G\rightarrow$ Gravitational force (the weight of the object). $f_k\rightarrow$ Kinetic friction force. $T\rightarrow$ Tension force.
b) The acceleration here is directed to the left since the net force is in the negative $ x$-direction.
c) The direction of the speed is toward the tension force, as we see in the figure below, which means toward the left.
The object is speeding up in the negative $x$-direction.
d) A car pulls a box with a rope toward the west and the rope is unstretchable. See the second figure below.