Answer:
Show ΔBCD ≅ ΔGFE, so ∠C ≅ ∠F. Base angle of an isosceles triangle are congruent, so ΔACF is isosceles.
Step-by-step explanation:
Informally, subtract DE from CE and DF. This will show CD ≅ EF.
Then ΔBCD ≅ ΔGFE by the HL theorem for right triangles.
Corresponding parts of congruent triangles are congruent, namely the angles C and F.
Since base angles of ΔACF are congruent, it is isosceles.
You can find the area of a hemisphere by using the following equation
V = (2/3) (pi)*r^3
so V = (2/3) (pi)*1.6^3
Which comes out as 8.5786423394 or 8.6
