Can someone plz help its has numbers on it but there incorrect so plz tell e what the right answer is thank you

Determine whether the set of whole numbers is closed under addition. explain why the set is or is not closed. give an example.

Question 3(multiple choice worth 1 points) use the arc length formula and the given information to find r. s = 16 cm, θ = 48°; r = ? sixty divided by pi cm thirty divided by pi cm one third cm one hundred twenty divided by pi cm

What is the arc length of the subtending arc for an angle of 72 degrees on a circle of radius 4? o a. 8a oc. 16 t d. 8