Answer:
128805.2988 cm squared or 128000 to 3 significant figures.
Explanation:
Area of a circle : pi times radius squared or 
pi times 4.1×10^4 cm = 41000 pi or 128805.2988
Answer:
a. an increase in the mass on the spring.
Explanation:
T = 2π/ω = 2π/√(k/m) = 2π√(m/k)
2π is a constant
as m is in the numerator, increasing mass will increase the period.