1 0l irout welghts 1 U 405.5 grams? special food 1 pue T0lnbox trouliinacnings in 0 a standard deviallon of 10,8 1 1 Based = 1 onuiarge 1 H inesd Qulu 1...

${ }_{86}^{220} \mathrm{Rn} \rightarrow{ }_{94}^{216} \mathrm{Po}+{ }_{2}^{4} \mathrm{He}, \mathrm{t}_{1 / 2}=51.5 \mathrm{~s}$ ${ }_{81}^{216} \mathrm{Po} \rightarrow{ }_{82}^{212} \mathrm{~Pb}+{ }_{2}^{4} \mathrm{He}, \mathrm{t}_{1 / 2}=0.16 \mathrm{~s}$ ${ }_{82}^{212} \mathrm{~Pb} \rightarrow{ }_{83}^{212} \mathrm{Bi}+{ }_{-1}^{0} \mathrm{e} \quad, \mathrm{t}_{1 / 2}=10.6 \mathrm{~h}$ 10 minute after taking an initial sample of $\mathrm{Rn}$, the element with the greatest mass will be (a) $\mathrm{Rn}$ (b) Po (c) $\mathrm{Pb}$ (d) $\mathrm{Bi}$

Hello students. So in this question we have to determine one program per meter cube. It is equal to what? Okay so we have to convert these units because uh in the question in the options we have Graham or centimeter cube units. Okay so we will convert these units. So one program or meter cube. This can be written as this. Okay, so Desert is one and one program from the conversion table using one program this is equal to 1000 g and one m. It is equals 200 centimeters. Okay so substituting these conversing values here. So we will get that one more player by one program which is this 1000 g. They were by one m which is 100 centimeters 100 centimeters. And this cube. Okay so from here after solving we will get that we will get that. This value will be one by 1000 gram per centimeter cube. Okay so from the given options options second it is the correct answer for this problem. Okay so this becomes the answer for the given problem. Okay thank you.

In this question that grand must have given spaces should be calculated. A given number of month of Iran is It was 2 0.31 more more mass of idleness equals two 55. 185 rampart more. We know number of Morris is equals two. Must divided by more. Armas Therefore mask off. I don't is equal to number of most of either. My decried by more. Are myself Either Number of most of irony. 0.231 mall multiplied by moral mask. 55 1 85 grandpa More. Therefore this is equals two 18.5. Yeah, That's the grandmaster of. 0.31 more ironic 18.5 g. B given number of most of floating. Yes, equals two. 2.1 more more aromas of of three is equal to 19 grandpa more. Therefore mass of story is equals two number of most of fraud in and two moral myself for it. So this is a good number of moles of flooring is 2.1 more. Multiplied by Mama's 19 g. Far more. Therefore, this is equal to 40 grandpa. Sorry, 40 g. That's the grandmas of 2.1 more of Florence is 40 g. See given number of most of carbon dioxide Is the close to zero Do you know 34 more mama's well, carbon dioxide is equals two atomic mass of 51 last 22 atomic mass of oxygen. Therefore the physical stew atomic mass of carbon is 12.01. Yeah. Five more bus go into atomic mass of oxygen is 16 grandpa more. Therefore this is equals to 44 .01 from part That's more mass of carbon dioxide is 44.01 g par mode mass of Carbon dioxide is equals two. Number of moles. Oh, carbon dioxide indu model mass of carbon dioxide. This is the close to a number of moles of carbon dioxide is 0.03. four more. We'll do 44. 1 grand. Far more equals two. One point 50 g. Does The grandmas of 0.034 More. Carmody outside is 1.50. Sorry. Okay. Okay. The given number of laws. Oh, what a shame. Promet that is scared to fear of is equal stood 1.89 more mama's of what I'm saying? What I say? I'm from it. That is scared to see her or food equals two two and two atomic mass of of potassium. Yes. Atomic mass of from Yeah. Plus foreign to atomic mass of oxygen. This is equal stool doing to atomic mass of potassium is 39.1 grandpa are more plus atomic mass of From um is 52 rampell more. Yes, for into atomic mass of oxygen is 16 grandpa, remote equal stoop 1 94 1 2 g or More. Thus myself. What are some from it Is is equal to the number of moles multiplied by more. Alma's number of modes of potassium traumatised. 1.89 more Multiplied by moral masses. 1 94. I went to grandpa more equals two G 67. Yeah. Thus the dramas of 1.89 more potassium from eight is 67 g.

High advanced in this question, they asked calculating mass of one ft till anthem in a sample whose activities frequent sewn into rendition Back. Really given that its half life is 40 hour. Okay, so we know that okay is equal to half into W. Into a forgiveness number forms. Yeah. Mm. Mhm. Upon capital A so kids 3.7 into Tenders to 10. That is equal to be half 14-16-16 into W. Into forget. This number divided by 114 and therefore W is equal to 3.7 into two, understood 10 into 1, 40, wow. Divided by 40 into 60, into 60 W. 6.02 into $10 to 23. That is therefore W is equal to and yeah. Therefore W is equal to Yeah. Yeah. 1.79 into appendix two. Uh huh minus six grand Thanks

Well, everyone, this is Ricky and they were working on a problem. Five from a model test number six. And so this is a question asking us about sphere that's inscribed in a cube. And what the ratio of the falling sphere to the booth. All right, So to start this question, let's write down the formulas for both of our severe and for acute first fear, 4/3 choir cute. And for the volume of the Cube, a heart issues this will rather Cuba's the length aside. Yes, threes as cute. And then, if we translate this where the length of side ISS equal to the radius spear, get or rather the diameter of the spear, get what you are. That's a cute Wallace to paint way Now if we look at the ratio votes spear. Q. Start with Why are huge? Huge. You see that? Ready? I drop out. And for my what a fine two. Everything's fine Pi over 63.14 over six, which is about 0.52 I hope this video is helpful. Seeing that