Answer:
A) Distance time graph
B) d(t) = 25t
C) The expression shows the distance more clearly.
Step-by-step explanation:
A) A distance time graph as seen in the attachment provides a representation of the distance travelled.
We are told the car travels at a constant speed of 100 meters per 4 seconds. Which means that 100 m for each 4 hours. So, for 200m, it's 8 hours like seen in the graph and for 300m,it's 12 hours as seen in the graph.
B) And expression for the distance is;
d = vt
Where;
d is distance in metres
v is speed in m/s and t is time
We are told that the car travels at a constant speed of 100 meters per 4 seconds.
Thus, v = 100/4 = 25 m/s
Distance travelled over time is;
d(t) = 25t
C) Looking at both A and B above, it's obvious that the expression of the distance shows a more clearer way of getting the distance because once we know the time travelled, we will just plug it into the equation and get the distance. Whereas, for the representation form, one will need to longer graphs if the time spent is very long.
20
Step-by-step explanation:
Step 1:
Let the number be 50 and to find 40% of 50 is given interms of expression as follows
To express the percentage the following strategy is used
Eg: 40% = 
∴ To express 40% of 50 is

Step 2:
On simplification the above expression we could get

= 20
You have to do 12 times 4, which equals 48. So 48 pounds in a year. 105 plus 48 would be 153 so that would be his weight by next year
Locate 1 on the x axis. This is the horizontal number line.
Draw a vertical line through 1 on the x axis. Extend this vertical line as far up and down as you can.
Notice how the vertical line crosses the blue curve. Mark this point. Then draw a horizontal line from this point to the y axis. The horizontal line will touch -4 on the y axis. So that means the point (1,-4) is on the curve.
If the input it is x = 1, then the output is y = -4
So that's why the answer is choice A