Answer:
Broad sense heritability A.K.A (H) is the degree in which phenotypic variation is due to genetic factors
Narrow sense heritability A.K.A (h) is the degree in which phenotypic variation is due to additive genetic factors.
in maths terms...
H = Vg/Vt
h = Va/Vt
Vg= genetic varaition
Vt = total variation
Va = additive variation