What is the difference between the numbers? What number comes next? Complete the table: Subtract from the given number.

1a.
$5, 7, \square$

Step 1: Calculate the difference.
$7 - 5 = 2$

Step 2: Add the difference to the last term.
$7 + 2 = 9$

Next number: 9
$\boxed{9}$

1b.
$10, 20, \square$

Step 1: Calculate the difference.
$20 - 10 = 10$

Step 2: Add the difference to the last term.
$20 + 10 = 30$

Next number: 30
$\boxed{30}$

1c.
$135, 235, \square$

Step 1: Calculate the difference.
$235 - 135 = 100$

Step 2: Add the difference to the last term.
$235 + 100 = 335$

Next number: 335
$\boxed{335}$

1d.
$284, 304, \square$

Step 1: Calculate the difference.
$304 - 284 = 20$

Step 2: Add the difference to the last term.
$304 + 20 = 324$

Next number: 324
$\boxed{324}$

1e.
$414, 516, \square$

Step 1: Calculate the difference.
$516 - 414$
$516 - 400 = 116$
$116 - 14 = 102$

Step 2: Add the difference to the last term.
$516 + 102$
$516 + 100 = 616$
$616 + 2 = 618$

Next number: 618
$\boxed{618}$

1f.
$474, 674, \square$

Step 1: Calculate the difference.
$674 - 474 = 200$

Step 2: Add the difference to the last term.
$674 + 200 = 874$

Next number: 874
$\boxed{874}$

2. Complete the table.

For $164 - 1$:
$164 - 1 = 163$

For $164 - 10$:
$164 - 10 = 154$

For $327 - 1$:
$327 - 1 = 326$

For $327 - 10$:
$327 - 10 = 317$

Completed table:

$\boxed{\begin{array}{c|c|c} 164 & 163 & 154 \\ 327 & 326 & 317 \end{array}}$