Answer:
a.

b.

Explanation:
Given

Solving (a): Round to the nearest hundredth thousandth
This means there would be 5 digits after the decimal.
So:
-- (approximated)
(b) Express in standard form
A number in standard form has the following format;

Where

So:

becomes

This is because the decimal point was moved 5 places backwards
Approximate 4.167 to nearest integer; We have:
