331. Спрости вираз:
1) 8 ⋅ 7 ⋅ х; 2) 17х ⋅ 2; 3) 5 ⋅ х ⋅ 9 ⋅ m;
4) 9а ⋅ 11b; 5) 5 ⋅ х ⋅ 9 ⋅ 8 ⋅ а ⋅ т; 6) 10b ⋅ 20с ⋅ 17р.