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Answer:
Absolute error 
% Error
5
Explanation:
The absolute error is the the difference in the measured value and the actual value of a quantity.
Here the actual value is
grams
The measured value is
grams
Absolute error

Percent error

Where AE stands for absolute error and AV stands for absolute value.

%
The average speed of the family : 70 km/h
<h3>Further explanation</h3>
Given
time = 2 hour
distance = 140 km
Required
The average speed
Solution
Distance is the length traveled by an object within a certain time
Average speed = total distance/total amount of time
Can be formulated :
Avg speed = d : t
Total distance traveled : 140 km
Total time : 2 hr
Avg speed = 140 : 2 = 70 km/h