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Nezavi [6.7K]
1 year ago
6

L.F. Richardson proposed a model to describe the spread of war fever. His proposal: If y(t) is the percent of the population adv

ocating war at time t, then the rate of change of y(t) at any time is proportional to the product of the percentage of the population advocating war and the percentage not advocating war. Set up a differential equation that is satisfied by y(t). (Note: Use k for the constant of proportionality with k > 0.)y' = ____________ , k > 0
Mathematics
1 answer:
Lena [83]1 year ago
8 0

Answer:

y'(t)=ky(t)(100-y(t))

Step-by-step explanation:

The rate of change of y(t) at any time is the derivative of y with respect to time y, y'(t)

If y(t) is the percent of the population advocating war at time t

then 100-y(t)  is the percent of the population not advocating war

The product of the percentage of the population advocating war and the percentage not advocating war would be

y(t)(100-y(t))

If the rate of change of y(t) at any time is proportional to the product of the percentage of the population advocating war and the percentage not advocating war, then

y'(t)=ky(t)(100-y(t))

where <em>k is the constant of proportionality </em>

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PART I
Angular size of the minor arc . 
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Therefore, using trigonometric ratio, sine = opp/hyp
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Therefore, the angular size of the minor arc will be 53.13 × 2  = 106.26°

PART II
The length of an arc is given by (θ/360 )× 2πr
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8 0
2 years ago
Desiree works 28 hours per week. She has a monthly income of $120 from investments. Desiree also plays in a band one night a wee
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So hmmm let's see
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her total annual income is 49696, now, if we subtract the band and investment income, we'd be left over with only what comes from her job payrate
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now, she only works 28 hours weekly, how much is that yearly?   well, 52 weeks in a year, she works 28*52 hours a year, let us divide 37856 by that

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2 years ago
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Answer:

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Answer:

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