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
The answer is. $1500.
Let x represent the amount invested at 5%, then is the amount invested at 8%, and is the amount invested at 6%. Since the total return is $1270:
let money invested at 5%= x
money invested at 6%
= 20000- (X+X-1500)
21500-2x
Total interest for 1 year.
x×5/100+ (x-1500)×8/100+(21500-2x)×6/100 = 1270
5x/100+8(x-1500)/100+(21500-2x)6/100=1270
5x+8x-12000+129000-12x = 127000
x+117000 = 127000
x = 10000
money invested at 8%
=21500-2×10000
= 1500.
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Answer:
5 tacos for 2 guests would mean more for each person, while 2 tacos for 5 guests would mean less for each person
Answer:
Simplifying the expression: 
we get 
Step-by-step explanation:
We need to simplify the expression:
First we will solve terms inside the bracket
Converting mixed fraction 
into improper fraction, we get: 
Replacing the term:
Now, taking LCM of: 5,3,4,2 we get 60
Now multiply 60 with each term inside the bracket
Now, combine like terms
Now, multiply all terms with 2
So, Simplifying the expression: we get
