A particle passes from one end of a laboratory to the other in 4.2×10⁻⁸ seconds as observed by a scientist who is stationary with respect to the lab. That scientist measures the lab to be 10m long. In the frame of the particle, the length of the lab is measured to be closest to:
A) 10m.
B) 8m
C) 6m
D) 12.5m
(E)) 16.6m