Answer:
± 25
Step-by-step explanation:
Answer yes 569
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Answer:
The difference between city and town is 189m.
Step-by-step explanation:
A city is 138m above sea level and town is 51m below see level.
When finding the differences, you have to take the highest value and subtract the lowest value :

Let bob score =x
according to given condition
(3x-40)/2=100
3x-40=200
3x=240
x=80
so bob score =80