Well to find this out you need to make an equation
s+7=j
So for example if Johnny's sister is 15 then Johnny would be 22 because
s(sister's age) +7(number of years difference between their ages)=22(Johnny's age)
Answer:
Human activities may affect the physical environment, and the physical environment may affect human activities.
Explanation:
Geography is everything to human activities. The Fertile Crescent is incredibly important for the start of civilizations. Humans also affect the environment, like deforestation and mining.
There are three meanings.
1. the process or fact of isolating or being isolated.
2. denoting a hospital or ward for patients with contagious or infectious diseases.
3. an instance of isolating something, especially a compound or microorganism.
What’s the question and isn’t this a maths question??
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