Cohesion known as water attraction to other water molecules is one of the major properties of water. liquid water has surface tension. this allows for insects such as water striders to walk on water. question number 3 the answer is because ice is less dense then liquid water because the water molecules for a new large structure as they cool down. of course Lakes freeze a course from top down even though the coldest areas are at the bottom. cold water begins to rises when it begins to freeze it accumulates at the top with a sheet of ice. the ice provides some insulation for the water below so that there is typically a significant portion of water under the ice sheet unless it's extraordinary really cold for a very very very very long time. if a lake froze from the bottom up they would more than likely freeze completely
Student 1’s methods would be more accurate, because the student would control more factors. Only one variable at a time (either temperature or acidity) would be tested on each group of worms. On the other hand, Student 2 is testing both factors on all the worms, which could make the results unclear.
