Post $AB$ is supported by a ball and socket at A and two cables as shown.

a$.(5$ points$)$ How many unknowns are in this problem?

i$.2$

ii$.3$

iii. $4$

iv$.5$

v$.6$

vi$.7$

b$.(15$ points$)$ What is the tension in each cable?

CABLE LEIGTHS

$BC=\sqrt[\phantom{2}]{(-2{)}^2+(3{)}^2+(-6{)}^2}=7m$

$BD=\sqrt[\phantom{2}]{(2{)}^2+(3{)}^2+(-6{)}^2}=7m$