Answer:
- <u>59.0891 g (rounded to 4 decimal places)</u>
Explanation:
<em>Half-life time</em> of a radioactive substance is the time for half of the substance to decay.
Thus, the amount of the radioactive substance that remains after a number n of half-lives is given by:
Where:
- A is the amount that remains of the substance after n half-lives have elapses, and
- A₀ is the starting amount of the substance.
In this problem, you have that the half-live for your sample (polonium-210) is 138 days and the number of days elapsed is 330 days. Thus, the number of half-lives elapsed is:
- 330 days / 138 days = 2.3913
Therefore, the amount of polonium-210 that will be left in 330 days is:
Since it is a parallelogram cente at point T,
then the measure of PT is equal to the measure of TR. And the measure of QT is
equal to the measure of TS.
PT = TR
a + 4 = 2a
4 = 2a -a
a = 4
PT = TR = 8 units
QT = TS
b = 2b -3
3 = 2b – b
b = 3
<span>QT = TS = 3 units</span>
Break it down into 2-Dimensional shapes. Then add the areas together.
From the picture you can see;
front & back rectangles are 2*(4 x 8) = 64 m²
2 side rectangles are 2*(4 x 12) = 56 m²
2 triangular front & back pieces are (1/2)*8*3 = 12 m²
2 roof rectangles are 2*(5 x 12) = 120 m²
total Surface area = 64 m² + 56 m² + 12 m² + 120 m²
= 252 m²
For the volume; break it up into 3-dimenssional shapes and add the volumes together.
From the picture you can see;
Rectangular box volume is 4 x 8 x 12 = 384 m³
Triangular roof volume is area of front triangle multiplied through the length. (1/2)*8*3* 12 = 144 m³
Total volume = 384 m³ + 144 m³
= 528 m³
There is no picture to look at
