[tex]\color{plum}\tt \: D) 38.5 [/tex]
Diameter of the stained glass window Joey needs = 3.5
Area of the window = quantity of glass Joey needs
Area of the window :
[tex] = \tt\pi {r}^{2} [/tex]
[tex] = \tt3.14 \times 3.5 \times 3.5[/tex]
[tex] =\tt 3.14 \times 12.25[/tex]
[tex] =\tt 38.46[/tex]
38.46 can be rounded off to 38.5.
Therefore, quantity of glass needed to make the stained glass window = 38.5
