Cobalt has an atomic number (Z) of 27, which means the nuclei of all its isotopes have 27 protons. Cobalt 60 has an atomic mass of 60, so it has 60-27 = 33 neutrons.
The mass of 27 isolated protons plus the mass of 33 isolated neutrons would be:
27*(1.007825 u) + 33*(1.008665 u) = 60.497220 u
The actual mass of the nucleus of 60-Co is 59.933820 u.
Mass defect: 60.497220 u - 59.933820 u = 0.563400 u
The mass defect is equal to the binding energy of a nucleus.
using the fact that 1 u = 931.5 MeV/c^2
(0.563400 u)*(931.5 MeV/u) = 524.807 MeV
Answer:
7.64% probability that they spend less than $160 on back-to-college electronics
Step-by-step explanation:
Problems of normally distributed samples can be solved using the z-score formula.
In a set with mean
and standard deviation
, the zscore of a measure X is given by:

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.
In this problem, we have that:

Probability that they spend less than $160 on back-to-college electronics
This is the pvalue of Z when X = 160. So



has a pvalue of 0.0763
7.64% probability that they spend less than $160 on back-to-college electronics
Answer:
18 cents per ounce
Step-by-step explanation:
The first step is to identify the unit. In this case, you are told you have 16-ounces. Therefore, your unit is an ounce.
To find the price of one ounce, just divide your price of $2.88 by 16.
Unit rate = $2.88 / 16 = 0.18 or 18 cents per ounce.