30 POINTS! A coconut falls 18 m from the top of a palm tree. How fast will the coconut be traveling when it reaches the ground? (Hint: KEinitial = 0, PEfinal = 0.)
A. 19 m/s
B. 13 m/s
C. 9.4 m/s
D. 27 m/s

Consider the growth of a 20-nm-diameter silicon nanowire onto a silicon wafer. the temperature of the wafer surface is maintained at 2400 k. assume the thermal conductivity of the silicon nanowire is 20 wm-1k-1 and all its surfaces including the tip are subjected to convection heat transfer with the coefficient h = 1×105 wm-2k-1 and t∞ = 8000 k. when the nanowire grows to l = 300 nm, what is the temperature of the nanowire tip (t (x =