Henry constructed circle a with a radius of 4 units. he then created a sector as shown in the figure below. which of the following expressions would him find the area of the shaded sector?

The picture in the attached figure

we know that
area of a sector=(∅*pi/360°)*r²--------> when ∅ is in degree

in this problem
∅=120°
r=4 units
so
area of a sector=(120°*pi/360°)*4²-------> (120°/360°)*(16*pi) units²

The expressions to find the area of the shaded sector is
(120°/360°)*(16*pi) units²

(1/3)*(16*pi)----> (16/3)*pi units²

the area of the shaded sector is  (16/3)*pi units²