Final answer:
The best estimate for the value of 'r' in the scatter plot is 0.7.
Step-by-step explanation:
The best estimate for the value of 'r' in the scatter plot is a) 0.7.
The value of 'r' is always between -1 and +1, and it represents the strength of the linear relationship between two variables. Values of 'r' close to 1 indicate a stronger positive correlation, while values close to -1 indicate a stronger negative correlation.
In this case, none of the other options (-0.5, 1, 0) are closer to 1 than 0.7, so the best estimate for 'r' is 0.7.