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11.Taking 5 minute shower instead of 10 minute shower.

12.They allow dangerous ray from sun into earth.

13.they help scientist compare elements in the rock.

Explanation:

I'm not sure about number 13

the cladogram shown here shows similarities and differences among several classes of vertebrates. anatomically, the four have limb structure as their common ancestor. we might separate the mammals from the other three classes because they a) divergent; do not lay eggs b) identical; are warm-blooded c) varied; a four chambered heart d) homologous; have mammary glands