What is the drawback of the linear model? A.
communication is only in one direction
B.
too much noise is created
C.
no feedback is sent on receiving the message
D.
long travel between the sender and the receiver

long travel between the sender and the receiver

long travel between the sender and the receiver

Explanation:

only #2 represents an object at rest on a table.

in #1, there is no normal force due to the table; the object is accelerating downward.

in #3, the vertical forces are not balanced; the object is accelerating downward.

in #4, neither the vertical nor the horizontal forces are balanced. the object is accelerating upwards and to the right.