Answer:
5)102,78
6)56,56
<em><u>See</u></em><em><u> </u></em><em><u>THE</u></em><em><u> </u></em><em><u>IMAGE</u></em><em><u> </u></em><em><u>FOR</u></em><em><u> </u></em><em><u>SOLUTION</u></em><em><u> </u></em>
Alrighty
squaer base so length=width, nice
v=lwh
but in this case, l=w, so replace l with w
V=w²h
and volume is 32000
32000=w²h
the amount of materials is the surface area
note that there is no top
so
SA=LW+2H(L+W)
L=W so
SA=W²+2H(2W)
SA=W²+4HW
alrighty
we gots
SA=W²+4HW and
32000=W²H
we want to minimize the square foottage
get rid of one of the variables
32000=W²H
solve for H
32000/W²=H
subsitute
SA=W²+4WH
SA=W²+4W(32000/W²)
SA=W²+128000/W
take derivitive to find the minimum
dSA/dW=2W-128000/W²
where does it equal 0?
0=2W-1280000/W²
128000/W²=2W
128000=2W³
64000=W³
40=W
so sub back
32000/W²=H
32000/(40)²=H
32000/(1600)=H
20=H
the box is 20cm height and the width and length are 40cm
Answer:
in *42* days it will be 45 seconds behind
Step-by-step explanation:
it is already 3 behind and if its only 1 second everyday then you add 1 day until you get to 45 which 42+3 is 45 so the correct answer is 42 days.
