Using the following public datasets from GCP Bigquery, identify the percentage of US population that is residing in the following air quality zones, leveraging latest available data:

Air Quality	% Population
AQI 0 -50	?
AQI 51-100	?
AQI 101-150	?
AQI > 150	?

Datasets

bigquery-public-data:epa_historical_air_quality.o3_daily_summary

bigquery-public-data:geo_census_blockgroups. us_blockgroups_national

`bigquery-public-data.census_bureau_acs.blockgroup_2018_5yr`

Explain the query.