A student investigated the heat loss of livestock in wet vs dry conditions using beakers of hot water to represent the animals. One beaker was wrapped in wet fleece (representing wet coat conditions in the rain) and another was wrapped in dry fleece (representing dry coat conditions). Both beakers were filled with the same volume of hot water and their temperatures were recorded at intervals of 20 minutes over 40 minutes. This was repeated for five trials. The results are shown below:
| Trial | Wet coat - 0 min | Wet coat - 20 min | Wet coat - 40 min | Dry coat - 0 min | Dry coat - 20 min | Dry coat - 40 min |
|---|---|---|---|---|---|---|
| 1 | 80 | 48 | 31 | 80 | 65 | 53 |
| 2 | 78 | 46 | 29 | 78 | 63 | 51 |
| 3 | 82 | 50 | 32 | 82 | 67 | 55 |
| 4 | 79 | 47 | 30 | 79 | 64 | 52 |
| 5 | 81 | 49 | 31 | 81 | 66 | 54 |
How many times did the student measure the temperature of the water in the beakers under wet coat conditions during the entire investigation?
The diagram below shows one of the temperature readings during the investigation.
Use the diagram and the information in the table to complete the following sentence:
"The reading on this thermometer is …\dots… …\dots… …∘C\dots ^\circ\text{C}…∘C, which suggests the reading was taken from a beaker after …\dots… …\dots… …\dots… minutes kept under …\dots… …\dots… …\dots… coat conditions."
What was the independent variable (the variable that the student chose to change) in this investigation?
What was the dependent variable (the variable measured by the student) in this investigation?
Explain why the student kept other variables constant.
Give one way that the student could make these temperature measurements more accurate.
The results of this investigation suggest that livestock production (such as growth or milk yields) would be less efficient if farmers kept their animals in wet, unsheltered outdoor areas rather than dry, sheltered areas. Use the data and your biological knowledge to explain why.
