A rock sinks straight down the surface of a pond, starting from rest and accelerating at an average rate of 2m/s^2 for the first 3 seconds of its motion. At the 3-second mark, the rock reaches its terminal speed and continues at that speed for the remaining 30 meters of motion. What is the total time it takes for the rock to sink from the surface to the bottom of the lake?

Ithink the answer would be a

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 valence of an element or radical is equal to the number of positive or negative charges on the ion.