So there are a totally of 52 cards right?(not counting jokers because jokers are not in official cards)
And there are 4 aces right?
So there are 52 outcomes and 4 of them are aces.
So when we write probabilities we write it in fraction form where the total number of outcomes is the denominator and the ones you want to get are the numerator OK?
So the total number is outcomes is 52 and becomes the denominator and 4 the number of aces become the numerator.
So 4/52 right?
And we now have to simplify it right?
And so we divide by the highest common factor right?
In this case 4 because there isn’t other numbers that are factors and greater than 4.
So 4 divided by 4/52 is 1/13 right?
4 goes into 4 1 time and 13 times into 52.
So your answer is 1/13
the 3rd one. hope this helps
Answer:
The correct answer is:
Between 600 and 700 years (B)
Step-by-step explanation:
At a constant decay rate, the half-life of a radioactive substance is the time taken for the substance to decay to half of its original mass. The formula for radioactive exponential decay is given by:

First, let us calculate the decay constant (k)

Next, let us calculate the half-life as follows:

Therefore the half-life is between 600 and 700 years
8.60 cm is the answer to your question and i used calculator.net for help