Explicación paso a paso : a)Dato.
Longitud de la circunferncia = L = 37, 68cmπ = 3, 14Formula.
L = 2 π * r 37, 68cm = 2 * 3, 14 * r37, 68cm = 6, 28 * r37, 68cm / 6, 28 = r6cm = rFormula.
Area del circulo = AcAc = π * r²Ac = 3, 14 * (6cm)²Ac = 3, 14 * 36cm²Ac = 113, 04cm²b)L = 94, 2pulπ = 3, 14Formula.
Longitud de la circunferencia = L = 2 * π * rL = 2 * π * r94, 2pul = 2 * 3, 14 * r94, 2pul = 6, 28 * r94, 2pul / 6, 28 = r15pul = rArea Circulo = AcAc = π * r²Ac = 3, 14 * (15pul)²Ac = 3, 14 * 225pul²Ac = 706, 5pul²c)L = 21, 98cmπ = 3, 14Formula.
L = 2 * π * r21, 98cm = 2 * 3, 14 * r21, 98cm = 6, 28 * r21, 98cm / 6, 28 = r3, 5cm = rFormula.
Ac = π * r²Ac = 3, 14 * (3, 5cm)²Ac = 3, 14 * 12, 25cm²Ac = 38, 465cm²d)L = 40, 82mπ = 3, 14L = 2 * π * r40, 82m = 2 * 3, 14 * r40, 82m = 6.
28 * r40, 82m / 6, 28 = r6, 5m = rAc = π * r²Ac = 3, 14 * (6, 5m)²Ac = 3, 14 * 6, 5m * 6, 5mAc = 3, 14 * 42, 25m²Ac = 132, 665m²El último ejercicio lo dejo para que practique sigues el mismo procedimiento.