Answer:
Explanation:
The total area of metal discs is given by:
total area = area of one disc * number of discs
The area of one disc is given by:
A = 2πrh + πr^2
where r is the radius and h is the thickness.
Substituting the given values, we get:
A = 2π(0.75 cm)(0.2 cm) + π(0.75 cm)^2
= 0.3π cm² + 0.5625π cm²
= 0.8625π cm²
The number of discs melted can be found by dividing the total area by the area of one disc:
number of discs = total area / area of one disc
number of discs = 508.68 cm² / 0.8625π cm²
number of discs ≈ 185.