Heat engines are less than 100% efficient because absolute zero cannot be reached
Answer:
(a) 34.47 cm
(b)
south of west
Explanation:
Let us draw a figure representing the individual displacement vectors in the four jumps as shown in the figure attached with this solution.
Now, let us try to write the four displacement vectors in in terms of unit vectors along the horizontal and the vertical axis.

Now, the vector sum of all these vector will give the resultant displacement vector.

Part (a):
The magnitude of the resultant displacement vector is given by:

Part (b):
Since the resultant displacement vector indicates that the final position of the vector lies in the third quadrant, the vector will make some positive angle in the direction south of west given by:

Answer:
C: A snow sled going down hill
Answer:
parabolic path
Explanation:
As the cart reaches the end of the table with a horizontally directed velocity (only horizontal component), the cart will follow a parabolic path given by the combined action of:
(1) kinematic equation for motion under constant velocity in the horizontal direction (linear expression in terms of time), and
(2) kinematic equation for motion under constant acceleration (that of gravity) in the vertical direction (quadratic expression in terms of time)