9a projecting front of a mountain (4) - P*** - is it 'peak'? 19d all square up and down (5) - ***E* - is it 'level'? 12a 1980s sitcom could be smoother, too (4,2,5) - ***E *O *O*S* - is it 'home to roost'? 3d suffer tough tests as a croquet ball? (2,7,5) - *O *H***** H***S - is it 'go through hoops?