Organising the data: 
The heights of plants in containers A and C decreased an average height of 3.5cm after vinegar was added to them. The stems of plants in containers A and C were weak and the plants could not stand upright.
whereas
The plants in containers B and D continued to grow healthily, increasing an average height of 2.5cm with water given every day. The stems of the plants in containers B and D were strong and the plants were still upright.