Answer:
t ≈ 0.0664731
Explanation:
Use the inverse sine function.
sin(12t) = 141/197
12t = arcsin(141/197)
t = arcsin(141/197)/12
t ≈ 0.0664731 . . . . . . . radians
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This is the principal value. There are other solutions at values of t that have integer multiples of π/6 added to this. There are also solutions where any of those values is subtracted from π.
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In general, angles in math are assumed to be in radians, unless specified otherwise. This angle corresponds to about 3.81°. (In geometry, the usual assumption is that angles are measured in degrees.)