Answer:
The maximum error in the calculated in the area is about 
The relative error is 0.02
The percentage error is 1.82%
Step-by-step explanation:
(a) Differentials are infinitely small quantities. Given a function
we call
and
differentials and the relationship between them is given by,

Let
be the radius of the disk and its area
. If the error in the measured valued of
is denoted by
, then the corresponding error in the calculated value of A is
, which can be approximated by the differential

We know that
and
, substituting into the above differential we get

The maximum error in the calculated in the area is about 
(b) The definition of relative error is

To find the relative error you need to divide the error by the total area

(c) To find the percentage error you need to apply this formula

