|axb|= |a*b|*sin(90°)=3*4*1=12
80 пудов- 100\%
1) 126 : b = 21
b = 126 : 21
b = 6
2) y : 16 = 64
y = 1024
3) 187 : в = 17
в = 187 : 17
в = 11