Answer
(a) (i) the Picard is longer
(b) $2.3$
Work Step by Step
(a) We know that the length of ship P is contracted by a factor of $\gamma=\frac{1}{\sqrt{1-\frac{v^2}{c^2}}}$ observed by a person in the ship L. Thus, the actual length of the ship P is greater than that of ship L. Thus, the best option is option (i), that is, the Picard is longer.
(b) We know that $\frac{L_{\circ p}}{L_{\circ L}}=\frac{1}{1-\sqrt{\frac{v^2}{c^2}}}$
$\frac{L_{\circ p}}{L_{\circ L}}=\frac{1}{\sqrt{1-\frac{(0.90c)^2}{c^2}}}$
$\frac{L_{\circ p}}{L_{\circ L}}=2.3$
