1.d2.d3.d4.No. 1 empty:1(No.1) 2 (No.2) 3m3xy No.2 empty: mn-b (m+ 1). ÷2 5.65438 +0 empty: -7a 3b 2 empty: 4th empty: 5th empty: 4th empty: 4 6. Solution: 2+m+1= 6 ∴ m = 3 ∶ 3n+(5+1= 63n+3 = 6 ∴ n =17. Solution: a- 1=0.b+3=0. Solution: a= 1.b=-3 8. Substitute a= two sevenths into the algebraic expression -3ax 2-x+7. Original expression = 6/7 x 2-x+7 9. (1) direct answer: swimming area: mn rest area: a quarter of schools (pi 3. 14 15926-3. no longer