Alight-year is the distance that light travels in one year. the speed of light is 3.00 × 108 m/s. how many miles are there in one light-year? (1 mi = 1609 m, 1 y = 365 d)
a 5.88 × 1012 mi
b 9.46 × 1015 mi
c 5.88 × 1015 mi
d 9.46 × 1012 mi

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 =