A chemical reaction must occur for a compound to have different properties.
Answer:
Half life is 6 years.
Explanation:
T½ = In2 / λ
Where λ = decay constant.
But N = No * e^-λt
Where N = final mass after a certain period of time
No = initial mass
T = time
N = 0.625g
No = 10g
t = 24 years
N = No* e^-λt
N / No = e^-λt
λ = -( 1 / t) In N / No (inverse of e is In. Check logarithmic rules)
λ = -(1 / 24) * In (0.625/10)
λ = -0.04167 * In(0.0625)
λ = -0.04167 * (-2.77)
λ = 0.1154
T½ = In2 / λ
T½ = 0.693 / 0.1154
T½ = 6.00 years.
The half life of radioactive cobalt-60 is 6 years
Which surface ocean current has the warmest water.
The answer would be B
Nothing, he shouldn’t be able to move it. Think about it like this say you try really hard to push something that is 5,000 pounds and you push as hard as you can. Well you can’t move it bc it weighs more than you can push. I’m sure their is a equation you can use to see how much you can push (body weight=force?)
The coefficient of performance (cop) of a refrigerator is defined as the ratio of " the work necessary to heat or cool something usefully."
The usable heating or cooling delivered to work required ratio, also known as the coefficient of performance, or COP, of a heat pump, refrigerator, as well as air conditioning system. Higher efficiency, less energy (power) usage, and thus reduced operational costs are all related to higher COPs.
Coefficient of performance formula:

where, K = Coefficient of performance,
= heat of pumps output,
= work required by the system.
It is refrigeration's coefficient of performance (COP) will always be greater than 1.
Therefore, the coefficient of performance (cop) of a refrigerator is defined as the ratio of " the work necessary to heat or cool something usefully."
To know more about coefficient of performance
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