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Across
  1. 3. The term used for a building/complex of buildings containing several individually owned apartments or houses.
  2. 4. The use of which type of energy is a good way to try to make your house sustainable?
  3. 6. Best known for his role on Entourage, this actor-turned-environmentalist completely rebuilt a 160-year-old Brooklyn brownstone for his mother keeping sustainability in mind.
Down
  1. 1. This Nordic country has been ranked as the happiest country in the world to live in as per the World Happiness report 2021.
  2. 2. This building material is responsible for 7% of global CO2 emissions, more than what comes from all the trucks in the world.
  3. 5. The Museum of Tomorrow that features sustainable design, incorporating natural energy and light sources is a science museum of which South American country?