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:
80cause there are 80 sides
Answer:
B
Step-by-step explanation:
....................
Answer:
C. 500 + 300 + 50 + 10 + 7
Step-by-step explanation:
Which expression represents the number 867?
A. 80 + 60 + 70
B. 800 + 6 + 7
C. 500 + 300 + 50 + 10 + 7
D. 500 + 300 + 60 + 70
Checking the answer choices by adding the expression
A. 80 + 60 + 70
= 210
No correct
B. 800 + 6 + 7
= 813
Not correct
C. 500 + 300 + 50 + 10 + 7
= 867
Correct
D. 500 + 300 + 60 + 70
= 930
Not correct
Therefore option C. 500 + 300 + 50 + 10 + 7 is the correct answer
<span>6-t/2t+9 = -2
multiply both sides by 2t+9
which will give you
6-t= -2(2t+9)
6-t = -4t + 18
now add 4t to both sides
6 -t + 4t = -4t -18 + 4t
6 + 3t = -18
6-6 + 3t = -18 -6
3t = -24
t = -24/3
t= -8 (negative 8)
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