There are 4 shapes on a 10x10 grid. Which shape is closest to the green 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: green right_triangle at (9, 5)
Distance from target shape to cyan right_triangle at (4, 6): 6
Distance from target shape to red square at (2, 2): 10
Distance from target shape to yellow right_triangle at (9, 9): 4
Closest shape is the yellow right_triangle at (9, 9) with distance 4</think>

<answer>(9, 9)</answer>