If $2 \cos ^2 \theta+3 \cos \theta=2$, then permissible value of $\cos \theta$ is

A line makes angles $\alpha, \beta, \gamma$ with the co-ordinate axes and $\alpha+\beta=90^{\circ}$, then $\gamma=$

The equations of planes parallel to the plane $x+2 y+2 z+8=0$, which are at a distance of 2 units from the point $(1,1,2)$ are

If $X$ is a.r.v. with c.d.f $F(x)$ and its probability distribution is given by

then, $F(1.5)-F(-0.5)=$