Step by step solution :
standard deviation is given by :
where, 
is standard deviation
is mean of given data
n is number of observations
From the above data, 
Now, if 
, then 
If 
, then 
if 
, then 
If 
, then 
If 
, then 
so, 
No, Joe's value does not agree with the accepted value of 25.9 seconds. This shows a lots of errors.
Answer:
C. 28.09 amu
Explanation:
The natural occurring element exist in 3 isotopic forms: namely X-28 (27.977 amu, 92.23% abundance), X-29 (28.976 amu, 4.67% abundance) and X-30 (29.974 amu, 3.10% abundance).
The atomic weight of elements depends on the isotopic abundance. If you know the fractional abundance and the mass of the isotopes the atomic weight can be computed.
The atomic weight is computed as follows:
atomic weight = mass of X-28 × fractional abundance + mass of X-29 × fractional abundance + mass of X-30 × fractional abundance
atomic weight = 27.977 × 0.9223 + 28.976 × 0.0467 + 29.974 × 0.0310
atomic weight = 25.8031871 + 1.3531792 + 0.929194
atomic weight = 28.0855603 amu
To 2 decimal place atomic weight = 28.09 amu
Hi pupil here's your answer ::
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How does Newton's second law of motion gives the measurement of force?
So the answer is first : what is newton's second law? =》The rate of change of momentum of an object is equivalent to particular direction of the FORCE
=> This is how Newton's second law of motion gives the measurement of FORCE .
=>It gives measurement as the equation
》 F=MA《
Where F is force , M is mass of the object , and A is the acceleration produced .
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hope that it helps. . . . . .
When the iron bar is placed within the coils of a solenoid it then becomes a magnet.
It is the most massive planet in the solar system.
