Your answer would be $4 times $y.
Hope this helps; have a great day!
Answer:
C. Use of a semi permeable membrane.
Explanation:
This techniques improves water taste and odour. It also helps to remove contaminant from water and also impurities. it is effective and safe to use and the system is fully automated and it works as a filtration technique.
Your answer is nitrogen fixing bacteria
let me know if you have any further questions
:)
