Answer: D. All variables are measured to provide data for the experimental results
Explanation:
In an experiment, variables are changed from one part of the experiment to another to see the change in effect so option A is incorrect.
Not all variables are changed in experiments. Only independent variables are changed so that their differential effects on the dependent variable is measured. Option B is therefore incorrect.
Not all variables affect the results o the experiment so option C is incorrect as well.
Variables are indeed measured so that data is produced for the results which would enable conclusions to be made so option D is correct.
Answer:
The answer is C. Petri Dish because a beaker, flask and graduated cylinder all hold liquid and can be transferred.
Factors that determine the rate of stream erosion-
➡️ Rainfall (more rain more erosion). ✔️
➡️water velocity ✔️
➡️shape, size and depth of channel ✔️
➡️stream capacity to transport eroded material, and the nature of the material being transported✔️
➡️Gradient (Steepness or slope) ✔️
➡️Discharge (Amount of water carried at a given time) ✔️
➡️Load (The materials carried by a stream)
Rainfall (more rain more erosion). ✔️
➡️Slope (the steeper the slope the faster the water will flow) ✔️
➡️Geology (if the bedrock is a soft silt it will erode faster than granite).✔️
Answer:
Natural selection and selective breeding can both cause changes in animals and plants. The difference between the two is that natural selection happens naturally, but selective breeding only occurs when humans intervene. For this reason selective breeding is sometimes called artificial selection.
Explanation: