Answer:
Distance between A and B is 5400 meters
Step-by-step explanation:
Consider "D" the letter to identify distance between A and B
Let's use "t" to identify the time of the first encounter (Devi and Kumar), and create an equation that states that the distance covered by Devi (at 100 m/min) in time "t", is equal to the total distance D minus what Kumar has covered at his speed (80 m/min) in that same time:
Recall that distance equals the speed times the time:
distance= speed * time
First encounter:
100 * t = D - 80 * t
180 * t = D Equation (1)
Not, 6 minutes later (at time t+6) , Devi and Li Ting meet .
Then for this encounter the distance covered by Devi equals total distance d minus the distance covered by Li Ting:
100 *(t+6) = D - 75 * (t+6)
100 t + 600 = D - 75 t - 450
175 T + 150 = D Equation (2)
Now, let's equal equation (1) to equation (2), since D should be the same:
180 t = 175 t + 150
5 t = 150
t = 30
Then the time t (first encounter) is 30 minutes. Knowing this, we can use either equation to find D:
From Equation (1) for example: D = 180 * t = 180 * 30 = 5400 meters
A function m(t)= m₀e^(-rt) that models the mass remaining after t years is; m(t) = 27e^(-0.00043t)
The amount of sample that will remain after 4000 years is; 4.8357 mg
The number of years that it will take for only 17 mg of the sample to remain is; 1076 years
<h3>How to solve exponential decay function?</h3>
A) Using the model for radioactive decay;
m(t)= m₀e^(-rt)
where;
m₀ is initial mass
r is rate of growth
t is time
Thus, we are given;
m₀ = 27 mg
r = (In 2)/1600 = -0.00043 which shows a decrease by 0.00043
and so we have;
m(t) = 27e^(-0.00043t)
c) The amount that will remain after 4000 years is;
m(4000) = 27e^(-0.00043 * 4000)
m(4000) = 27 * 0.1791
m(4000) = 4.8357 mg
d) For 17 mg to remain;
17 = 27e^(-0.00043 * t)
17/27 = e^(-0.00043 * t)
In(17/27) = -0.00043 * t
-0.4626/-0.00043 = t
t = 1076 years
Read more about Exponential decay function at; brainly.com/question/27822382
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First count the number of digits after the first one 6 This = 6 and is the exponent of 10 so the required notation is
6.000370 * 10^6
Answer:
15
Step-by-step explanation:
500-60=440
440/30=14.66666667
simplify 14.66666667= 15
