A. Identify how the electrostatic force acts between protons, and between protons and each of the other two types of particles that make up atoms. (4 points) b. Identify the element whose atoms have 9 protons. Is it a metal, a nonmetal, or a metalloid? Write 1 - 2 sentences describing how an atom of this element changes when it forms an ionic bond. (4 points)

Asteel tube (k=50 w/mk) of inner and outer diameter di = 20mm and do=26mm, respectively, is used to transfer heat from hot gases flowing over the tube (h-hot = 200w/m2k) to cold water flowing through the tube (h-cold = 8000 w/m2k). what is the cold-side overall heat transfer coefficient uc? to enhance heat transfer 16 straight fins of rectangular profile are installed longitudinally along the outer surface of the tube. the fins are equally spaced around the circumference of the tube, each having a thickness of 2mm and a length of 15mm. what is the corresponding overall heat transfer coefficient uc? *solve for uc in both cases*