Let
e1 be the eccentricity of the hyperbola
16x2−9y2=1 and
e2 be the eccentricity of the ellipse
a2x2+b2y2=1,a>b, which passes through the foci of the hyperbola. If
e1e2=1, then the length of the chord of the ellipse parallel to the x-axis and passing through (0, 2) is: