1. where chemicals pass between cells and blood platelets 2. an atmospheric gas expelled by body cells ventricle 3. a vessel that carries blood away from the heart cells 4. the liquid that carries chemicals and blood cells through the circulation alveoli 5. air sacs within the lungs plasma 6. a lower part of the heart blood vessels 7. any of the arteries, veins or capillaries that carry blood through the body serum 8. vessels that carry blood back to the heart atrium 9. an upper part of the heart trachea 10. need food and oxygen to live artery 11. the thin-walled tube which carries air from the nose and mouth into the lungs red blood cells 12. the liquid part of blood left over after clotting has taken place carbon dioxide 13. to stop bleeding veins 14. carry oxygen to the cells and take carbon dioxide away capillaries 15. the body fight infection white blood cells

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.

causes

fossil fuels burn

cities become more industrialized

human population grows worldwide

it's when something is going so fast it makes a loud noise, breaking the sound barrier, for example: a jet makes a loud noise, not only cause of the jet but because they reached a point where they went so fast that you can year the noise from various parts, kinda like a police car, lets say the car was going   so fast that you hear the siren of the cop car right next to you, but the car is probably a mile a way, it's cos the siren was next to you a few seconds if you understand me

the maxium height is 34m/s