Efectuati
a) {-16/33:8/7:[5/24:(3/8-1/3)+5/3]}:7/5
b)3/4×{2-5/6:[5/4-2:(3,4×5/17+2)]}
c)(2,75-1,25)×(11/18-1/9+(2la a2)totu la a3×[(1-1/2)la a3]totu la a2