The image of this question is missing and so i have attached it.
Answer:
dd/dt = 4.47 ft/s
Step-by-step explanation:
From the image attached, let's denote the following;
d = horizontal distance beneath pulley
h = height of pulley
l = diagonal from the pulley to the head of the person
v = velocity of rope rising
Using pythagoras theorem;
l² = d² + h²
Differentiating with respect to time and considering h = c^(te) gives;
2l(dl/dt) = 2d(dd/dt)
We are given;
d = 20 ft
h = 10 ft
v = 4 ft/s
We know that velocity in this case is change in diagonal distance with time. Thus;
v = dl/dt = 4 ft/s
From earlier, we saw that;
2l(dl/dt) = 2d(dd/dt)
Thus, reducing it gives
(dl/dt)(l/d) = dd/dt
Now, l² = d² + h²
l = √(d² + h²)
Also, v = dl/dt = 4
Thus;
4(√(d² + h²))/d = dd/dt
4(√(20² + 10²))/20 = dd/dt
dd/dt = 4.47 ft/s
I= PRT
7280=26000×0.07T
7280\1820=1820T\1820
4=T
dats all
9514 1404 393
Answer:
WX = 33
(x, y) = (2, 10)
Step-by-step explanation:
The hash marks tell you WX is a midline, so has the measure of the average of the two bases.
WX = (PQ +SR)/2 = (27 +39)/2 = 66/2
WX = 33
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The hash marks also tell you ...
PW = WS
y +4x = 18 . . . . . . substitute the given expressions
and also
QX = XR
2y +x = 22 . . . . . substitute the given expressions
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If you solve the first equation for y, you get ...
y = 18 -4x
Substituting that into the second equation gives ...
2(18-4x) +x = 22
36 -7x = 22 . . . . . . . simplify
14 = 7x . . . . . . . . . . . add 7x-22 to both sides
2 = x . . . . . . . . . . . . divide by 7
y = 18 -4(2) = 10 . . . find y using the above relation
The values of x and y are 2 and 10, respectively.
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My favorite "quick and dirty" way to solve a set of linear equations is using a graphing calculator. It works well for integer solutions.
The correct answer is C because they are asking for the specific screening kit marks
The percentage of the radioactive isotope left is 25.0000%.
<h3>What is the half life?</h3>
The half life of a radioactive isotope is the time that will elapse before only half of the number of original isotopes will remain.
Now;
We are told that;
Half life (t1/2) = 55 days
Time taken (t) = 115 days
Ratio of isotope remaining = N/No
Thus;
N/No = (1/2)^t/t1/2
N/No = (1/2)^115/55
N/No = (1/2)^2
N/No =1/4
Hence, the percentage = 1/4 * 100/1 = 25.0000%
Learn more about half life of an isotope:brainly.com/question/16387602
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