Answer: The correct option is (B) 1.28 radians.
Step-by-step explanation: We are given that for an angle A :
[tex]\cos A=0.29.[/tex]
We are to find the measure of angle A in radians.
We know that the relation between degree and radians is given by
[tex]80^\circ=\pi~\textup{radians}\\\\\\\Rightarrow 180^\circ=\dfrac{22}{7}~\textup{radians}.[/tex]
Now, we have
[tex]\cos A=0.29\\\\\Rightarrow A=\cos^{-1}(0.29)\\\\\\\Rightarrow A=73.14^\circ.[/tex]
Again,
[tex]180^\circ=\dfrac{22}{7}\\\\\Rightarrow 1^\circ=\dfrac{22}{7\times180}\\\\\Rightarrow 73.14^\circ=\dfrac{22}{1260}\times73.14=1.277=1.28~\textup{radians}.[/tex]
Thus, the measure of angle A in radians is 1.28 radians.
Option (B) is CORRECT.
