For a concrete gravity dam with a triangular section, check the stability of a dam for rotation and overturning, translation and sliding and overstress and material failure for a normal loading condition. Design measure to make the dam safe against sliding, overturning (e. g., allocating drainage gallery, using grout curtain, pretension, and downstream supporting shoulder)

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. 

Answermake them get very hot and over time wear them out;

Dshould be the right answer i think