Which statement is completely accurate?

a. atoms of the same element always have different numbers of neutrons.
b. atoms of the same element always have different atomic weights.
c. atoms of the same element can have neutrons but exist without proton.
d. atoms of the same element can have different number of neutrons.

The transfer of heat through the movement of a gas or liquid a. convection b. conduction c. radiation

Write a polynomial function with the given zeros x= -1,0,2show your work

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*