The Figure Shows a Right-Angled Construction Frame $A B C$ When Measured at Rest, It Has Dimensions as Follows

Multiple Choice

The figure shows a right-angled construction frame $A B C$ . When measured at rest, it has dimensions as follows: $A B = 18.9 \mathrm {~m} , A C = 10.0 \mathrm {~m}$ , and $B C = 16.0 \mathrm {~m}$ . This frame is now given a new velocity of $0.420$ c, relative to Earth, in a direction parallel to $A C$ . How long is part $B C$ of this frame with the new velocity as measured by Earth-based engineers?

A) $16.0 \mathrm {~m}$
B) $10.0 \mathrm {~m}$
C) $12.0 \mathrm {~m}$
D) $18.0 \mathrm {~m}$
E) $14.0 \mathrm {~m}$