Lining up for Line Graphs

THIS PROBLEM IS A DRAFT IDEA - PLEASE CONSIDER ONLY WITH CAUTION!

 
Can you match these variables with the graphs that measuring them would produce? Are they what you would expect from reading the statements? Are they all related by a formula or are some lines of best fit? How do you know? Why might you draw a line of best fit rather than joining all of the points on a graph up?


1) Number of molecules of salt in a beaker vs reading when you put the beaker on a scale
 
2) Area of forest vs number of trees in it
 
3) Amount of force you need to apply to make an object move at 1mph vs mass of object
 
4) Amount of force you need to make an object move at 5mph vs mass of object

5) Amount of force you need to make an object move at 10mph vs mass of object

6) Temperature of tea vs time it has been cooling
 
7) Height of a dog vs its weight

8) Distance from sun vs temperature (what might happen if you extended this graph really far?)
 
9) Length of the sides of a square vs area of the square
 
10) Length of the sides of a cube vs volume of cube?
 
How can you use graphs to make estimations or predictions? Are there some times when these predictions are more reliable than others?