I need help solving and understanding this question!!!
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Answer:
h = 3589.9 meters ⇒ answer (D)
Step-by-step explanation:
∵ P(h) = P0 . e^(-0.00012h)
∵ P(h) = 65% of P0
∴ [tex]0.65P_{0}=P_{0}.e^{-0.00012h}[/tex]
∴ [tex]0.65=e^{-0.00012h}[/tex]
∵ Insert ln in both sides
∴ [tex]ln(0.65) = ln(e^{-0.00012h}) = -0.00012h(lne)[/tex]
∵ ln(e) = 1
∴ h = ln(0.65)/-0.00012 = 3589.9 meters