Two cylindrical wires are made of the same metal. If wire 2 has 8 times the length and 10 times the diameter of wire 1.?

R = ρ (length/area)

Let L and d be the length and diameter of wire 1.
Then, the length of wire 2 is 8L, and the diameter is 10d.

Then, R₁ = ρ {L/[π(d/2)²] = 4ρL/(πd²)
and R₂ = ρ {8L/[π(10d/2)²] = (8/25)ρL/(πd²)

R₂/R₁
= [(8/25)ρL/(πd²)] / [4ρL/(πd²)]
= (8/25) / 4
= (8/25) × (1/4)
= 2/25

R2/R1 = (L2/L1)/(d2/d1)² = 0.08