Which procedure is following when using the scientific method to solve a problem? Question 12 options: Identify something thought to be true and then set out to prove it. Identify a question, make observations, create a hypothesis, and then set up an experiment to test the hypothesis. Find something scientists say is true and then ask questions about it. Do an experiment and then ask questions about it.

The second one

Explanation:

Identify a question, make observations, create a hypothesis, and then set up an experiment to test the hypothesis.

answer: the correct answer is 1.

explanation: there are various process in which a radioactive nuclei decays:

1) alpha decay: in this process, a heavier nuclei decays into lighter nuclei by releasing alpha particle. the mass number is reduced by 4 units.

2) electron capture: in this decay process, a parent nuclei absorbs an electron and gets converted into a neutron. simply, a proton and an electron combines together to form a neutron. mass number does not change in this process.

3) gamma ray emission: it is a decay process in which an unstable nuclei gives excess energy by a spontaneous electromagnetic process. this decay releases . this process does not change the mass number.

4) positron emission: it is a type of decay process, in which a proton gets converted to neutron and an electron neutrino. this is also known as -decay. in this the mass number remains same.

from the above information, we see that only alpha-decay is producing a change in the mass number of the nucleus.