Step-by-step explanation:
We know that if an arc subtends an angle of theta , with a radius r , then the measure of arc is r× theta . Here theta is 109° .
[tex]\implies l = r\theta \\\\\implies l = r\times 109^{\circ}\\\\\implies l = r \times \dfrac{109}{180}\pi rad \\\\\implies \boxed{\boxed{ l = 0.6\pi r m }}[/tex]
where r will be the radius .
