Many stories are possible. Here is one of them:
Question 2 a) 1 +
2 x 3 + 4 +
5 x 6 +
7 x (2 + 3 x 4)
Note: 3 x 4 is underlined TWICE, once for being part of the 7 x ( . . .) bundle and again for being a separate multiplication bundle (a simple bundle) inside the brackets.
b) The value of the expression is: 139
Question 3
2 + 3 x 10 ÷ 6 - 4 x 1 + 28 ÷ 4 + 2 x [3 + 4 x (10 - 2 x 3)],
Way #1 (work out the simple multiplication bundles first & then process the brackets, etc.)
2 + 5 - 4 + 7 + 2 x [3 + 4 x (10 - 6)]
2 + 5 - 4 + 7 + 2 x [3 + 4 x 4]
2 + 5 - 4 + 7 + 2 x [3 + 16]
2 + 5 - 4 + 7 + 2 x 19
2 + 5 - 4 + 7 + 38
2 + 5 - 4 + 7 + 38
48
Way #2 (process from right to left, dealing with multiplication bundles in turn)
2 + 3 x 10 ÷ 6 - 4 x 1 + 28 ÷ 4 + 2 x [3 + 4 x (10 - 6)]
2 + 3 x 10 ÷ 6 - 4 x 1 + 28 ÷ 4 + 2 x [3 + 40 - 24]
2 + 3 x 10 ÷ 6 - 4 x 1 + 28 ÷ 4 + 2 x 19
2 + 3 x 10 ÷ 6 - 4 x 1 + 28 ÷ 4 + 38
2 + 3 x 10 ÷ 6 - 4 x 1 + 7 + 38
etc.
48