1, 2, and 3
hope it helps next time upload with picture
Answer:
The basic steps of the scientific method are: 1) make an observation that describes a problem, 2) create a hypothesis, 3) test the hypothesis, and 4) draw conclusions and refine the hypothesis.
As can be seen in the attached image, α-pyrone has a highly electrophilic carbon atom, since it is attached to two oxygen atoms that are electronegative and subtract electrical charge from the carbon, leaving it with a <u>positive partial charge</u>. By virtue of the above, <u>the bromine atoms, which have an important electron density that makes them good nucleophiles, will be attracted to the aforementioned carbon due to their positive charge</u>, thus favoring the substitution product to a greater extent than that of addition.
A doesn't change the model, that's what google's for, B can be easily used with the current model, and D is ridiculous.
The model of, for example, the atom, has changed over the years with multiple experiment sand multiple models. There was plum pudding, for example, with protons and electrons scattered throughout, until Rutherford's experiments (a new discovery) changed that because he found a dense nucleus.
The answer pops out at you