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2 years ago

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]2 years ago

4 0

Answer: 2 half-life periods

and 6 days

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On circle OOO below, the measure of \stackrel{\LARGE{\frown}}{FJ} FJ ⌢ F, J, start superscript, \frown, end superscript is 84^\c

lianna [129]

Answer:

100°

Step-by-step explanation:

The angle between chords is the average of the intersected arc angles.

∠FKJ = ½ (84° + 76°)

∠FKJ = 80°

∠HKJ is supplementary to ∠FKJ.

∠HKJ = 180° − 80°

∠HKJ = 100°

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2 years ago

Which proportion satisfies the geometric mean (altitude) theorem for the triangle?

Degger [83]

D is the correct answer

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2 years ago

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If m< LMP is 11 degrees more than m< NMP and m< NML =137, find each measure

Agata [3.3K]

First, note that for angles LMP and NMP you have

$m\angle LMP+m\angle NMP=m\angle NML.$

If $m\angle LMP$ is $11^{\circ}$ more than $m\angle MNP,$ then

$m\angle LMP=m\angle NMP+11^{\circ}.$

Now, since $m\angle MNL=137^{\circ},$ you have

$137^{\circ}=m\angle NMP+11^{\circ}+m\angle NMP,\\ \\2m\angle NMP=137^{\circ}-11^{\circ}=126^{\circ},\\ \\m\angle NMP=63^{\circ}.$

Therefore,

$m\angle LMP=63^{\circ}+11^{\circ}=74^{\circ}.$

Answer: $m\angle LMP=74^{\circ},\ m\angle NMP=63^{\circ}.$

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2 years ago

During an experiment, Juan rolled a six-sided number cube 18 times. The number two occurred four times. Juan claimed the experim

Maru [420]

Answer:

1) Juans claim is incorrect. The correct experimental probablilty is 2/9

Step-by-step explanation:

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2 years ago

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You found $6.60 on the ground at school, all in nickels, dimes, and quarters. you have twice as many quarters as dimes and 42 co

Veseljchak [2.6K]

Let the number of nickels found be n, the number of dimes be d and the number of quarters be q.

i) "you have twice as many quarters as dimes and 42 coins in all."

means that 2d=q, and n+d+q=42

we can reduce the number of unknowns by substituting q with 2d:

n+d+q=42
n+d+2d=42
n+3d=42

We can write all n, d and q in terms of d as follows:

there are n=42-3d nickels, d dimes and q=2d quarters.

ii) In total there are $6.60 dollars,

1 nickel = 5 cent = $0.05
1 dime = 10 cent = $0.1
1 quarter = 25 cent = $0.25

thus

(42-3d)*0.05 + d*0.1 +2d*0.25= $6.60

2.1 - 0.15d+0.1d+0.5d=6.60

2.1+0.45d=6.6

0.45d=6.6-2.1=4.5

d=4.5/0.45=10

iii)

so, there are 10 dimes, 2d=2*10=20 quarters and 42-3d=42-3*10=12 nickels.

Answer: 10 dimes, 20 quarters, 12 nickels

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2 years ago