22 The diagram shows a triangular prism ABCDEF with a horizontal base ABEF.
12 cm
A
C
10 cm
F
B
D
12 cm
15 cm
E
Diagram NOT
accurately drawn
BE 15 cm
=
AC = BC= FD = ED = 12 cm
AB= 10 cm
Calculate the size of the angle between AD and the base ABEF.
Give your answer correct to 3 significant figures.
