The answer would be D hope it helps and sorry if it is wrong. :)
In an alpha decay, an atom emits an alpha particle. An alpha particle consists of 2 protons and 2 neutrons: this means that during this kind of decay, the original atom loses 2 protons and 2 neutrons from its nucleus.
This also means that the atomic number Z of the element (the atomic number is the number of protons in the nucleus) decreases by 2 units in the process, while the mass number A (the mass number is the sum of the number of protons and neutrons) decreases by 4 units.
Answer:
C is the best answer because we all know that clock is part of our daily lives but we don't know the about its background
Answer: C Plane
Explanation: According to Newton's law, gravitational force is proportional to the product of masses and inversely proportional to the square of distance between them.
Gravitational force depends on mass. The bigger the mass, the more the magnitude of the gravitational force. Since plane is assume to have the highest mass in the options, we can therefore conclude that plane will experience the highest gravitational force.