Answer:
The mass of the radioactive sample after 40 minutes is 12.8 g.
Step-by-step explanation:
The mass of the sample can be found by using the exponential decay equation:

Where:
N(t): is the amount of the sample at time t =?
N₀: is the initial quantity of the sample = 120 g
t = 40 min
λ: is the decay constant = 0.056 min⁻¹
Hence, the mass of the sample after 40 min is:

Therefore, the mass of the radioactive sample after 40 minutes is 12.8 g.
I hope it helps you!
The answer would be A. <span>The registration fee is $5.50, and the cost per download is $0.95.</span>
Solution
Let x = registration fee
y = cost/downloads
Jack
15y + x = 19.75 ; x = 19.75 - 15y
Jim
40y + x = 43.50
Thus,
40y + x = 43.50
40y + <span>19.75 - 15y = 43.50
</span>25y = 23.75
y= 0.95
for x,
<span>x = 19.75 - 15y</span>
x = 19.75 - 15( 0.95)
x= 19.75 -14.25
x = 5.5
Answer:
A. 4 1/2 ==+ 3
B. 2 + 4
C. 1/2 + 1/2
D. 2 1/2 + 1
E. 4 1/2 + 2
Step-by-step explanation:
Read the coordinates and just like figure out the order which it's like 1 through 5 but wit fractions. hope this helps.
……….. I’m sorry need points