The scientific method isa. the use of modern technology to understand the way the world worksb. the use of controlled laboratory experiments to understand the way the world worksc. the dispassionate development and testing of theories about how the world works. d. the search for evidence to support preconceived theories about how the world works. c

c. the dispassionate development and testing of theories about how the world works

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.

the electric field is a “force field” around a charged object that illustrates the direction the electric force would push an imaginary