Why the nail in the test tube 2 is not rusted ?

Scientist have long study the earths climate by looking at which of the following? the earths orbit. the earths rock layers. the antarctic ice. the earths oceans.

The following hormone had their receptors in the cell membrane except a-insulin b-tsh c-gh d- cortisol

Which of the following statements is most likely correct about a rock belonging to the jurassic age and a rock belonging to the cambrian age? options: 1) they have identical fossils of organisms that have evolved over time. 2) both have animal fossils preserved in them due to weathering and erosion. 3) they contain different fossils because life on earth has changed through time. 4) the fossils in them were formed on the surface of earth due to exposure to sunlight.