Which of the following explains why doctors practice antiseptic medicine? a.) to prevent patients from passing their illness to the doctor b.) to ensure that every patient receives enough antibiotics to kill all bacteria c.) to ensure that every patient has enough good bacteria to kill harmful bacteria d.) to prevent doctors from introducing microbes that could infect the patient

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. 

Answerthe distance between the two ends of the galaxy is 150,000 light years;