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Aleks [24]
2 years ago
9

a radioactive substance has a half-life of 2 seconds. A scientist begins with a sample of 20 grams. How much of the substance re

mains after 8 seconds?
Mathematics
1 answer:
s344n2d4d5 [400]2 years ago
5 0

Answer:

1.25 g

Step-by-step explanation:

you start with 20g at 0 seconds.

divide by half after 2 seconds and you have 10g.

at 4 seconds you have 5g.

at 6 seconds you have 2.5g.

at 8 seconds you have 1.25g.

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Zachary purchased a computer for 1800 on a payment plan. three months after he purchased the computer, his balance was 1350. fiv
nadezda [96]

(750m) - 1050 = b

1800 - 1050 = 750 dollars lost.

So (750m) - 1050 = b will give you the balance.


6 0
3 years ago
What is the sum of the geometric sequence-1 6 -36 yes there are 7 terms
vagabundo [1.1K]

Answer:

-39991'

Step-by-step explanation:

We require the sum of 7 terms of the G.S.  -1, 6, -36  .....

The common ratio r = 6/-1 = -6 and the first term = -1.

Sum of n terms = a1 . (r^n  - 1) / (r - 1)

Sum of 7 terms = -1 * (-6)^7 - 1)  / (-6 - 1)

=  -1 * 39991

= -39991 (answer).

7 0
3 years ago
Read 2 more answers
You have a basketball trophy in your room. The ball on the trophy has a diameter of 9 inches. What the volume of the ball?
saveliy_v [14]

Answer:

381.51 in^3

Step-by-step explanation:

Volume of a sphere = 4/3 x pi x r^3

r = 9/2 = 4.5

4/3 x 3.14 x 4.5^3 = 381.51 in^3

7 0
3 years ago
Y =3x+2 is the equation of a straight line graph.where does it cross the y-axis
neonofarm [45]
Cross the y-axis in x=0
therfore:
if x=0; y=3*0+2=2; ⇒ P(0,2)

solution: P(0,2).
7 0
3 years ago
Solve for the formula for the indicated variable. Solve A=1/2bh for b.
choli [55]
B = 2A/h

The way you would get this is first by clearing the fraction. So in order to clear the fraction, you have to multiply the equation by the denominator.

2(A = 1/2bh)

2A = 1bh

2A = bh

Then you have to isolate the variable. So you'd divide bh by h in order to get b by itself. So you'd end up with:

2A/h = bh/h

2A/h = b
5 0
3 years ago
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