The Unstable Isotope ²³⁴Th Decays by β Emission with a Half-Life

question 73

Short Answer

The unstable isotope ²³⁴Th decays by β emission with a half-life of 24.5 days. The initial decay rate of the sample was 9.9 × 10¹³ Bq. (1 u = 1.6605 x 10^-27 kg)
(a) What mass of ²³⁴Th was initially present?
(b) What is the decay rate after 68 days?

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Optimal Capital Structure

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Weighted Average Cost of Capital

A calculation of a firm's cost of capital that weights each category of capital proportionally, including equity and debt.

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