How
can it be proved that leaves
prepare food? Describe experiment.​

In the presence of starch iodine solution will turn into blue-black color and in the absence of starch iodine added to leaf will turn into brown color. ... So iodine added in this region will change into brown color. Thus this experiment proves chlorophyll is necessary for leaves to prepare starch through photosynthesis.

These acts all helped the countries form new states. These acts all helped to move frontiers further westward.

Explanation: