Answer:
v = 0.5 [m/s]
Explanation:
In order to determine the speed in such a time interval, we must calculate the slope between the last two positions.
The slope of a line is determined by the following mathematical expression.
P₂ = point 2 = (12,12) = (x₂,y₂)
P₁ = Point 1 = (6,9) = (x₁,y₁)
In this specific case, we must see that in the x-axis we have time, and on the y-axis, we have the space axis.
Now using the slope:

This slope is equal to the speed (velocity)
v = 0.5 [m/s]
Answer:
Net Force = 10 N
acceleration: 
Explanation:
1) The net force on the box is the applied force (F = 13 N) minus the friction force (f = 3 N), Therefore, net force = 10 N
See attached free body diagram.
2) To find the box's acceleration, we need first to find the mass of the box (since they are giving us its weight in Newtons). To do such we use the equation for weight and solve for the box's mass:

Now we can find the box's acceleration by using the equation for the net force:

help show if a straight "trend line" represents the experimental data
Can someone please answer this question I'm doing the test now?