See solution below
Work Step by Step
Observations are the first step in a scientific approach. The first observation that can be made is that the toast has not popped out of the toaster. The next step is a hypothesis (educated guess) to explain the observation. The hypothesis is that the spring mechanism is stuck. Next, there will be a test of the hypothesis. In this case, the test is an additional observation. The bread is unchanged meaning that it was not being cooked by the toaster. This observation leads to a new hypothesis, that the toaster is unplugged. This new hypothesis leads to additional tests to determine if the toaster is plugged in; and if it works when plugged into a different outlet. The final test on the toaster leads to a new hypothesis, that there is a problem with the power in the kitchen. This new hypothesis leads to the final test concerning the light in the kitchen.