Railroad crossing signs come in what two kinds of shapes? Octagon and equilateral triangle Circle and pentagon Circle and crossbuck Diamond and crossbuck

## Step 1<br />This problem is about the shapes of railroad crossing signs. The question asks us to identify the two shapes that are used for these signs.<br />## Step 2<br />The two shapes that are used for railroad crossing signs are the diamond shape and the crossbuck shape. The diamond shape is used for warning signs, while the crossbuck shape is used for regulatory signs.<br />## Step 3<br />The diamond shape is used for warning signs because it is easily recognizable and can be seen from a distance. The crossbuck shape is used for regulatory signs because it is more specific to the railroad crossing and can be seen more clearly from a distance.