The next term in the arithmetic progression is calculated by adding the common difference to the previous term.

Since A6=8 and A8=16, we can calculate the common difference as follows:

16 - 8 = 8

Therefore, the common difference is 8.

To find A1, we can use the formula for the arithmetic progression:

An = A1 + (n-1)d

Substitute n=6, A6=8, and d=8 into the formula:

8 = A1 + (6-1)8
8 = A1 + 40
A1 = 8 - 40
A1 = -32

Therefore, A1=-32.

To find d, we use the common difference we calculated earlier (d=8).

Therefore, d=8.

So, A1=-32 and d=8.