Answer:
The person should exercise 150 minutes
Explanation:
Recall that the Lorentz factor must be applied to the relationship between the elapsed time (T) of the clock at rest (time measured on Earth), and the elapsed time (T') measured by the clock in the frame moving at 0.8 c. The equation becomes:
[tex]T'=\frac{T}{\sqrt{1-(\frac{0.8\,c}{c})^2 } } \\T'=\frac{90\,min}{\sqrt{1-0.8^2} } \\T'=150\,\,min[/tex]
