There are 5 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, 6)
Distance from target shape to red square at (2, 2): 4
Distance from target shape to orange trapezoid at (5, 0): 9
Distance from target shape to blue rectangle at (1, 1): 6
Distance from target shape to gray trapezoid at (1, 8): 3
Closest shape is the gray trapezoid at (1, 8) with distance 3</think>

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