Pixabay
https://pixabay.com/illustrations/finance-dollar-currency-tree-apple-1577984/
https://pixabay.com/photos/industrial-buildings-warehouses-698563/
https://pixabay.com/photos/smoke-smoking-chimney-fireplace-258786/
https://pixabay.com/photos/glass-ball-autumn-tree-gnarled-1813707/
https://pixabay.com/vectors/recycling-recycle-waste-trash-99224/
https://pixabay.com/photos/environment-protection-earth-globe-3751682/
https://pixabay.com/photos/environmental-protection-326923/
https://pixabay.com/photos/earth-scion-leaf-sustainability-3289810/

Pexels
https://www.pexels.com/photo/group-of-people-enjoying-music-concert-325521/
https://www.pexels.com/photo/modern-businesswoman-in-casual-outfit-talking-on-mobile-in-office-4491469/
https://www.pexels.com/photo/man-holding-white-teacup-in-front-of-gray-laptop-842567/
https://www.pexels.com/photo/woman-wearing-gray-notch-lapel-suit-jacket-2381069/

unsplash
https://unsplash.com/photos/QdnS9Xjrn5Y
https://unsplash.com/photos/V4ZYJZJ3W4M
https://unsplash.com/photos/OnCwsPHn3Gw
https://unsplash.com/photos/QAxwYfxQYL4
https://unsplash.com/photos/XBxQZLNBM0Q

https://unsplash.com/photos/0Ksu8YIUg64
https://unsplash.com/photos/ESkw2ayO2As
https://unsplash.com/photos/IrGYJPF0JS0
https://unsplash.com/photos/LWDDtuCCEOE