Answer:
314 m
Explanation:
the diagonal is the hypotenuse of the two triangles that form the rectangle (see figure) we solve with Pythagoras
In a right-angled triangle, the square of the hypotenuse side is equal to the sum of squares of the other two sides
a² = b²+ c²
a² = 250² + 190²
a² = 62500 + 36100
a² = 98600
a = √98600
a = 314 m