A girl starts her bicycle from rest and accelerates uniformly to 7 m/s in a distance of 14 m. Calculate acceleration of the girl and time taken by her to travel the distance

Velocity is the speed of an object in a certain direction so you'd need to know speed and direction

You need to be more specific.  i really don't know what a "motion map" is.you can draw a graph of an object's position, distance, displacement, speed,velocity, or acceleration versus time, or you can draw a graph of the object's x-position versus its y-position and not give any information about time at all.if the graph presents position or displacement against time,  then constant velocity is a straight line . . i.e. a line that has  constant slope.if the graph shows speed against time, then constant velocityis a horizontal piece of line.if the graph shows acceleration against time, then constant  velocity is a piece of line that lies on the x-axis . . it's value is zero. 

Answershe should not have multiplied the sulfur atoms by the subscript 4