volume of container = 12 x 8.5 x 4 = 408 cubic feet
weight = 0.25 pounds per cubic foot
0.25 x 408 = 102 pounds
Point T is the midpoint of J and H.
x-coordinate is 0 for the three points.
y-coordinate of T is in the middle of the y-coordinate of J and the y-coordinate of H. So, y-coordinate of H has to be 6, because (6+2)/2=8/2=4.
Then point H is (0,6).
<span>D but i think you mean is x = (km-12)/6 got me confused :p </span>
Recall that for 3 vectors 
, all in 
, the vector triple product
So
Also recall the scalar triple product,
which gives the signed volume of the parallelipiped generated by the three vectors . When either 
or 
, the parallelipepid is degenerate and has 0 volume, so
and the above reduces to
so that
![(u\times v)\cdot[(v\times w)\times(w\times u)]=(u\times v)\cdot((v\times w)\cdot u)w](https://tex.z-dn.net/?f=%28u%5Ctimes%20v%29%5Ccdot%5B%28v%5Ctimes%20w%29%5Ctimes%28w%5Ctimes%20u%29%5D%3D%28u%5Ctimes%20v%29%5Ccdot%28%28v%5Ctimes%20w%29%5Ccdot%20u%29w)
The scalar triple product has the following property:
Since 
is a scalar, we can factor it out to get
and by the property above we have
and so we end up with
![[u\cdot(v\times w)]^2](https://tex.z-dn.net/?f=%5Bu%5Ccdot%28v%5Ctimes%20w%29%5D%5E2)
as required.
20.4 is the answer because there is 12 cm so you would multiply 12 by 1.7.
