D. friction pulls the skates wheels westward
When you expect something, but get something else, you have a reason big enough to ask new questions and start a new investigation.
Example:
If you create a tree by artificially breeding different species, and then plant it with certain expectations in width, size, bark width, leaf shape, etc. and things go differently, a new investigation might begin with a whole new load of questions.
Answer:

Hope it helped,
Happy homewok/ study/ exam!
Without a control group there wouldn’t be any basis for knowing if a result is due to the variable being tested
Answer:
it will dissolve
Explanation:
<em>CARRY </em><em>ON </em><em>LEARNING</em>
These preparations are called Vaccines. A vaccine is a biological preparation that provides active acquired immunity to a particular disease. A vaccine typically contains an agent that resembles a disease-causing micro-organism and is often made from weakened or killed forms of the microbe, its toxins or one of its surface proteins.