which is similar to n:1 where 
<u>Step-by-step explanation:</u>
Here we have to Express in the form n:1 give n as a decimal 21:12 . Let's find out:
Given ratio as 21:12 . Let's convert it into n:1 , where n is decimal
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{ dividing denominator & numerator by 4 }
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⇒ 
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which is similar to n:1 where 
Answer:
4/9
Step-by-step explanation:
Step-by-step explanation:
The formula for calculating a circle's circumference is πd, where π is an irrational number (3.14....) and d is the diameter of the circle.
In the circle with diameter 19.5cm, the circumference is around 3.14 * 19.5cm = 61.23cm. (A)
Hi I’m doing this for points
About 92 days are taken for 90 % of the material to <em>decay</em>.
The mass of radioisotopes (
), measured in milligrams, decreases exponentially in time (
), measured in days. The model that represents such decrease is described below:
(1)
Where:
- Initial mass, in milligrams.
- Current mass, in milligrams.
- Time constant, in days.
In addition, the time constant is defined in terms of half-life (
), in days:
(2)
If we know that
,
and
, then the time required for decaying is:






About 92 days are taken for 90 % of the material to <em>decay</em>.
We kindly invite to check this question on half-life: brainly.com/question/24710827