'The adjoining figure contains three squares with areas of 100, 16 and 49 lying side

"The
adjoining figure contains three squares with areas of 100, 16 and 49 lying
side by side as shown. By how much should the area of the middle square be
reduced in order that the total length `P Q`
of the
resulting three squares is 19?
`sqrt(2)`
(b) `2`
(c) 4 (d) 12"