How do present day scientists measure the depth of the ocean floor

What element is able to combine with itself and hydrogen to form large molecules ?

What condition is kept close to its set point in osmoregulation? a. body temperature b.platelet count c.blood glucose level d.water balance

Which best example best demonstrates the importance of having knowledge of evolutionary relationships? a. illustration of a plant b.organ transplantation between species c. blood donation from a human d. do you need sequence of an insect.