20.!!!!!!!!!!!!!!!!!!!!!!!!!!!!

1) (0,4*2,38-3,452):4ц.1/2-2ц.4/9=?
2) 2ц.5/14-2ц.1/4:(0,6*3,28-5,468)=?
3)(0,4*1,25-2,25):0,5-1/2=?
4) -2ц.1/4+0,54:(0,8*22,5-22,5=?