—Do you have Justin Bieber’s CDs ?

—Sorry, they ____. But we will get some more next week because they ____ .

A．sold out; are on sale

B．were sold out; sell well

C．were sold out; are sold well

D．sold out; sell well

如图，⊙O₁，⊙O₂的直径分别为1cm和1.5cm，现将⊙O₁向⊙O₂平移，当O₁O₂=（    ）cm时，⊙O₁与⊙O₂外切。