The opposite of zero is zero.

Use a number line to evaluate each of the following:

$(+7)+(+4)$

Use a number line to evaluate each of the following:

$0+(+6)$

Use a number line to evaluate each of the following:

$(+5)+0$

Use a number line to evaluate: $\left(-4\right) + \left(+5\right)$

Use a number line to evaluate: $\left(0\right) + \left(-2\right)$