Question

how does the water reach 180 meters high to the top of a tree like a eucalyptus

Answer 1

SIMPLY BECAUSE OF THE XYLEM TISSUES WHICH CONDUCT WATER TO THE SHOOT PART AND ALL THE REST PARTS OF THE PLANT. THE XYLEM TISSUE SHAVE TRACHEIDS AND VESSELS WHICH HELP IN CONDUCTING WATER.  THERE ARE XYLEM PARENCHYMA WHICH HELPS IN LATERAL CONDUCTION OF WATER. 

Answer 2

Transpiration creates a low pressure area in the bark and creates a suction area in the xylem vessels. This makes the water to rise up from the roots and therefore travel through all parts of the plants. Rrpeated transpiration means it can rise higher. Hope this will help you.