Final answer:
The width of the rectangle is 20 units.
Step-by-step explanation:
The area of a rectangle is given by the formula area = length x width. In this case, we know the area is 380 square units and the length is 19 units. To find the width, we can rearrange the formula as width = area ÷ length. So, the width of the rectangle is 380 ÷ 19 = 20 units. Therefore, the correct answer is a) 20 units.