I have a question that is giving me a bit of a hard time, here it is

Consider the problem of finding a path in the grid shown in Figure Ass-1 from the position s to the position g. A piece can move on the grid horizontally or vertically, one square at a time. No step may be made into a forbidden shaded area. enter image description here

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Using best-first search, nodes are expanding from s to g. Manhattan distance should be used as the evaluation function. The Manhattan distance between two points is the distance in the x-direction plus the distance in the y-direction. It corresponds to the distance travelled along city streets arranged in a grid. Assume multiple-path pruning. What is the first path found?

I tried the following approach but I am not sure since there are no give heuristic values
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any assistance will be appreciated