Which statement best explains why machines are inefficient? a. energy transfer in compound machines gives off electrical waste. b. during energy transfer in machines, some energy is always lost as heat. c. balanced forces in moving machines produce waste in the form of steam. d. when work is done by machines, gravity always causes a decrease in force.

The answer is a 0.64 volts

Ithink it is letter b, i may be wrong but i think that is the answer

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. 

Answermuch larger;