Answer:



Step-by-step explanation:
Given




Required
Determine the measure of each angle
The angles in a triangle sum up t 180. i.e.

Since
, then 
can then be rewritten as:


Substitute values for B and C

Open Bracket

Collect Like Terms


Divide both sides by 23

To get the measure of each angle, substitute 11 for x in the expressions of B, C and D









75 sq cm that should be right
The volume of a cuboid is the product of its dimensions.
(9.4 cm)·(5.4 cm)·(11.7 cm) = 593.892 cm³ ≈ 593.9 cm³