I did the math and I think that it's 3.7
Answer:
The incorrect statement is <em>A. Alpha and beta particles pose little or no hazard to human health.</em>
Step-by-step explanation:
Alpha particle - the nucleus of a helium atom, made up of two neutrons and two protons with a charge of +2. Certain radioactive nuclei emit alpha particles. Alpha particles generally carry more energy than gamma or beta particles, and deposit that energy very quickly while passing through tissue. Alpha particles can be stopped by a thin layer of light material, such as a sheet of paper, and cannot penetrate the outer, dead layer of skin. Therefore, they do not damage living tissue when outside the body. When alpha-emitting atoms are inhaled or swallowed, however, they are especially damaging because they transfer relatively large amounts of ionising energy to living cell.
Beta particles - electrons ejected from the nucleus of a decaying atom. Although they can be stopped by a thin sheet of aluminium, beta particles can penetrate the dead skin layer, potentially causing burns. They can pose a serious direct or external radiation threat and can be lethal depending on the amount received. They also pose a serious internal radiation threat if beta-emitting atoms are ingested or inhaled.
Therefore, <em>alpha and beta particles do pose affect the health of human beings.</em>
Answer:
207 minutes.
Step-by-step explanation:
115 x 4/5 = 92
115 + 92 = 207
Answer:
90
Step-by-step explanation:
make sure to use BIDMAS
start of by working out everything in the brakets first.
the first bracket would be 50
the second bracket would be -40
the minus these as there is a minus between the brackets
50--40=90
We need to first find a common denominator. This means that we need the 12 and the 3 to be the same number. We can change the 1/3 into 4/12 and see that 9/12 is larger than 4/12.