Arrange the following events in a correct order that explains the pressure flow of materials in the phloem.
1. Glucose is converted into sucrose.
2. Sucrose moves into the sieve tube cells by active transport.
3. Water moves from xylem into phloem by osmosis.
4. Hypertonic condition is created in phloem.
5. Leaf cells produce sugar by photosynthesis.
6. As osmotic pressure builds up, phloem sap moves to areas of lower pressure.