Answer:
The exact value of [tex]10\cdot a[/tex] is [tex]253.77^{\circ}[/tex].
Step-by-step explanation:
Sine function is a bounded function between -1 and 1 and positive in the first and second quadrants. From statement we deduct that [tex]a[/tex] is in the first quadrant, that is, [tex]0^{\circ}< A < 90^{\circ}[/tex]. Then, we determine the angle by inverse trigonometric function:
[tex]A = \sin^{-1} \frac{3}{7}[/tex]
[tex]A \approx 25.377^{\circ}[/tex]
Then, the exact value of [tex]10\cdot a[/tex] is [tex]253.77^{\circ}[/tex].