There are 4 shapes on a 10x10 grid. Which shape is closest to the yellow 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: yellow right_triangle at (2, 8)
Distance from target shape to red rectangle at (5, 3): 8
Distance from target shape to blue square at (1, 8): 1
Distance from target shape to pink right_triangle at (0, 0): 10
Closest shape is the blue square at (1, 8) with distance 1</think>

<answer>(1, 8)</answer>