Answer: The length of the arc is 1.57 centimeters
Step-by-step explanation: If the diameter has been given as 4 centimeters, then the radius would be diameter divided by 2, and that equals 2.
With the radius now known as 2, we can calculate the length of the arc as follows;
Length of an arc = (Ω/360) x 2πr
Where Ω is the angle subtended by the radio and r is the radius.
Length of an arc = (45/360) x 2 x 3.14 x 2
Length of an arc = (1/8) x 12.56
Length of an arc = 1.57
Therefore, the length of the arc is 1.57 centimeters