fermium-253 has a half-life of three days. a sample contains 400 g. how long will it take for the sample to decay to 100 g?

2 answers:

6 0

This is a relatively easy half life calculation.
After one half-life period, half of the isotope remains.
After two half-life periods, one quarter of the isotope remains.
That being the case, we see this will take 2 half-life periods or 6 days.

11111nata11111 [884]1 year ago

4 0

Answer: 2 half-life periods

and 6 days

You might be interested in

PLEASE help!!!! Jackie runs and dances for a total of 55 minutes every day. She dances 25 minutes more than she runs. Part A: Wr

Andrew [12]

Part a:

x + y = 55

y = x + 25

part b:

jackie runs 15 minutes every day.

part c:

it is not possible for jackie to spend 45 minutes a day dancing, since the time she spends dancing and running is 55 minutes, and we know that it takes 15 minutes to run

step-by-step explanation:

let's call and while jackie is dancing

let's call x while jackie is running

then we know that jackie runs and dances for a total of 55 minutes every day

this means that:

x + y = 55

we also know that jackie dances 25 minutes more than she runs.

this meant that:

y = x + 25

now we substitute the second equation in the first and solve for the variable x

x + x + 25 = 552x = 55-252x = 30x = 15

jackie runs 15 minutes every day.

now we find the value of the variable -y

15 + y = 55y = 55-15y = 40

note that it is not possible for jackie to spend 45 minutes a day dancing, since the time she spends dancing and running is 55 minutes, and we know that it takes 15 minutes to run

7 0

2 years ago

Read 2 more answers

4. In the following diagram, STU, RTP and

Papessa [141]

Yea I don’t know sorry bye

6 0

1 year ago

Andrew has a new job at the local pizza store as a delivery boy. The following graph shows one of his deliveries he made. Analyz

iren [92.7K]

B. 10 blocks
C. i’m not sure for this one but i’m guessing for directions
D. coming back

4 0

1 year ago

Form a sequence that has two arithmetic means between -1 and 59.

Oksanka [162]

The formula for solving the problem is as follow:
an = a1 + (n - 1)d
Where:
n = number of figure in the sequence = 4
d = difference between successive number =?
a1 = -1
a4 = 59
Insert the given values into the formula,
59 = -1 + (4 - 1)d
59 = -1 + 3d
59 + 1 = 3d
60 = 3d
d = 60/3 = 20
Therefore, d = 20. This implies that, there is a difference of 20 between successive numbers.
The number sequence is as follow:
-1, 19, 39, 59.

7 0

1 year ago

Read 2 more answers

The probability of drawing two aces from a standard deck is 0.0059. We know this probability, but we don't know if the first car

ivanzaharov [21]

Answer:

Option C is right

C. They are independent because, based on the probability, the first ace was replaced before drawing the second ace.

Step-by-step explanation:

Given that the probability of drawing two aces from a standard deck is 0.0059

If first card is drawn and replaced then this probability would change. By making draws with replacement we make each event independent of the other

Drawing ace in I draw has probability equal to 4/52, when we replace the I card again drawing age has probability equal to same 4/52

So if the two draws are defined as event A and event B, the events are independent

C. They are independent because, based on the probability, the first ace was replaced before drawing the second ace.

4 0

1 year ago