Which property of water do the water-striders (the insect and the robot) utilize in their aquatic-acrobatics?.

The authors use the word “backbone” in lines 3 and 39 to indicate that

Iknow this isn't a question, but is there someway to ask a question under public safety or is there no category for it? i don't know if i'm overlooking it or not.

This graph represents four ecosystems. each ecosystem has a different number of species, adding to its biodiversity. different colors represent different species. which statements correctly summarize the data depicted by the graph? 1. ecosystem d has more biodiversity than ecosystem c. 2. ecosystem b has more biodiversity than all the other ecosystems. 3. ecosystem a has more biodiversity than ecosystem b but less biodiversity than ecosystem c. 4. ecosystem b has more biodiversity than ecosystems c and d but less biodiversity than ecosystem a. 5. ecosystem a has more biodiversity than ecosystem c but less biodiversity than ecosystem b.