Who is the mutant sister of Quicksilver and half-sibling of Polaris?

Scarlet Witch

What fruit did Persephone eat that bound her to the Underworld for part of each year? What river in the Greek underworld was associated with forgetfulness? In "Thor: Ragnarok," which actor portrays the Grandmaster? Who performed the song "Shape of You"? In which country is Angkor Wat located?