What do you think,if two gl plates were dropped from exactly the same height over the same surface (cont.)?

If the gles had the EXACT same durability, which is hard since both gles probably have different chemical and physical makeups even if they are apparently the same , and if the ground that they hit is completely even,and if air resistance was even for both gles on the way down, then YES. This is because the same force would be applied over the same area (because both gles have the same acceleration and m at the point they hit the ground F=ma), and this would create the same even distribution of force in both plates, which would mean that they would break at the exact same points if each section of each plate had the same durability(durability meaning the amount of force that can be applied in a given area before breaking). Because the friction in each section of the plate is the same the same amount of energy in each section would be converted from potential (mgh) to kinetic energy(1/2mv^2) in the same exact way, so each shattered piece of each glass would be the same size and would fly in the exact same direction for the exact same distance in the exact same time.