-18+4x
2(2x-9)
4x=18
-4x=-18
x=18/4
-x=-18/4
A suitable calculator* can do this easily.
61°38'45" = (61 +(38 +45/60)/60)° ≈ 61.65°
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I like the RealCalc app for Android, but many graphing calculators also will do this conversion. Of course, you can simply evaluate the expression as above.
Answer:

Step-by-step explanation:
The time constant of the isotope is:


The decay of the isotope is described by the following model:

Now, the time is cleared in the equation:



350 divided by 7 is 50 so the man can run 50 feet in one minute