What is the change in internal energy if 30 J of heat are released from a system and the system does 50 J of work on its surroundings? Use AU= Q-W. O A. 20 J O B. -20 J O C. -80 J O D. 80 J​

No because scientist are still changing there mines today so they are not correct to this day

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. 

Electricity and discharge