There are 6 shapes on a 10x10 grid. Which shape is closest to the gray right_triangle in terms of Manhattan distance? The final answer is the grid position of the closest shape like (row_index, column_index).
<think>Target shape: gray right_triangle at (5, 3)
Distance from target shape to cyan square at (1, 4): 5
Distance from target shape to brown right_triangle at (3, 9): 8
Distance from target shape to blue right_triangle at (5, 0): 3
Distance from target shape to red trapezoid at (1, 0): 7
Distance from target shape to pink rectangle at (0, 1): 7
Closest shape is the blue right_triangle at (5, 0) with distance 3</think>

<answer>(5, 0)</answer>