Let's find the domain first :
h(x) = x + 2 ====》 D = R
g(x) = √x - 2 ===》 D : x -2 》 0
D : x 》2
The subscription of the domains of the g and h functions is equal to :
x 》2
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x = - 9 is not in the domain so the function value does not exist and option B is the correct answer.