According to one hypothesis, the jaws of vertebrates were derived by the modification of A) scales of the lower lip. B) skeletal rods that had supported pharyngeal (gill) slits. C) one or more gill slits. D) one or more of the bones of the cranium. E) one or more of the vertebrae.  

Which of the following is a characteristic of all chordates at some point during their life cycle? A) jaws B) post-anal tail C) four-chambered heart D) vertebrae

The detector solid angle (

Strongly bonded materials have higher stiffness.

For solid xenon, the bonding is covalent since xenon is an inert gas.

In order to obtain the most surface information on a sample with topographical contrast, all of the conditions below will improve this, except which one?

Hexagonal closed packed (HCP) structures follow ABCABCABC… packing sequence

Calculate the radius of a vanadium atom, given that V has a BCC crystal structure, a density of 5.96 g/cm3, and an atomic weight of 50.9 g/mol.

Index the illustrated directions in the unit cubic cell drawn below. 

Briefly define the following terms, concepts or rules using words, equations, and/or sketches: Valance electrons