Answer:
ys
Step-by-step explanation:
3,4×5,6×7,8×5,9
2 Simplify  4\times 54×5  to  2020.
3,20,6\times 7,8\times 5,93,20,6×7,8×5,9
3 Simplify  6\times 76×7  to  4242.
3,20,42,8\times 5,93,20,42,8×5,9
4 Simplify  8\times 58×5  to  4040.
3,20,42,40,93,20,42,40,9