WEBVTT
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in this question we want to find I want to
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see activity in the milk due to naturally occurring potassium
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. I settled right three assuming when he told me
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Has two grams off the rotation. So you're the
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first find Want to see number off rotation in money
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talks milk. So when he told milk two grams
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softball TZ um divided by D. Monem s off
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. What? A sandwiches to 9.1 grams football.
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So give us a number off Bulls quotation, multiplying
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Piety. Uh oh, God. Jesus. Number
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six point. You're to report any tree to get
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rusty number off new place. Not from here.
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We know that the isotope k 40 right? That
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is the rotation 40. There's not radioactive isotope.
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It's about 0.117% off the entire population off potential.
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So we can actually me that define this number off
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rotation 40 k 40 by multiplying in key. That's
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your point, Teoh. 117 percent right. Every
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shirt gets about 2.6 sent for 80 the cinema off
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radioactive new kites. Flotation 14 Your flights To fight
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e activity, we need to take the decay constant
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multiply party number off, Morticia. 40. Right
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. The decay constant is going to over the half
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Life you half life for petition for these given to
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be boat one point to it times 10 to the
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po. Off night. Yes. Multiplying this by
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she won 56 This will convert it from years.
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Two seconds. This number of seconds in the year
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. What everybody? A number of new kites,
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which is 3.6 step over 18. No activity.
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It's about 61.8. The case for a second or
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just cruise. Compare this to the amount of radio
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activity and milk which is due to the Odin.
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Just 2000 back rows. Right. This is a
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pretty small amount compared to the should have. Ah
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, extent that has costed increasing radio activity not to
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fight how long it would take before the activity to
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fall below that off deportation. But we know that
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the activity is boat. It starts right? Currently
40
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it's about 2000 back groups. Right? For one
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liter we wanted to drop to 61 point yet backhoes
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I saw a It goes to a not for my
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explanation agree from the tea that is by DTK law
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So, given that our we want our in the
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show to be 2000 final to be 61.8. So
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what if I d a Not over. I love
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50 exponential till on the right, you will take
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the natural lock on both sites. Gets negative love
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, not tea. So a t or be close
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to one over Lambda Times Lawn 2000 over 61 point
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. So basically the negative sign, cause I just
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divide by dated negative Lambda and the negative Lunda will
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cost the, uh no, Carrie don't function to
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flip de infection right now. What is the Lambda
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for duty, Right? This goes too long to
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three courses reversed. So, though, is t
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half over onto, but he her office about eight
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points. You're four days by long to we're evaluating
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this Ugo uncertainty in terms off days, which is
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40 point tree days.