I had that same answer, its on google just search it up.
Answer:

Step-by-step explanation:
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The sum of any geometric sequence, (technically any finite set is a sequence, series are infinite) can be expressed as:
s(n)=a(1-r^n)/(1-r), a=initial term, r=common ratio, n=term number
Here you are given a=10 and r=1/5 so your equation is:
s(n)=10(1-(1/5)^n)/(1-1/5) let's simplify this a bit:
s(n)=10(1-(1/5)^n)/(4/5)
s(n)=12.5(1-(1/5)^n) so the sum of the first 5 terms is:
s(5)=12.5(1-(1/5)^5)
s(5)=12.496
as an improper fraction:
(125/10)(3124/3125)
390500/31240
1775/142
Initial Conditions:
length=L= 10 cm = (10*10⁻²)m
Diameter=D= 2 cm= (2*10⁻²)m
Radius= r= 0.01m
Area=A= π*r²/2 =1.57*10⁻⁴ m²
Resistance=R= 600 ohm
So, from initial conditions we find resistivity(р)
R=рL/A
R*A /L=р
(600)*(1.57*10⁻⁴)/(10*10⁻²)=р
р=0.942 Ω m
<span>As, material remains same so resistivity(p) doesn't change
</span>Lenght= L1= 15 fm= 15*10⁻¹⁵ m
Diameter= D1 = 5 cm= 5*10⁻² m
Radius= r= 0.025 m
Area= A1= π*r²/2 =9.8125*10⁻⁴ m²
R=р*L1/A1
R=(0.942 )*(15*10⁻¹⁵ )/(9.8125*10⁻⁴)
R=1.44*10⁻¹¹ Ω
Total cans on bottom 4 shelves = 29 x 4 = 116
total cans on top 3 shelves = 42 x 3 = 126
total cans = 116 + 126 = 242 cans
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used cans = 56
remaining cans = 242 - 56 = 186 cans
number of cans in each shelf = 9
number of shelves = 186/9 = 20 and 6 cans remaining
remaining 6 cans will be displayed in another shelf
total shelves = 20+1 = 21