2. (6 points) The body mass index (BMI) of a person is defined as
I
=
W H2'
where W is the body weight in kilograms and H is the body height in meters. Suppose that a boy weighs 34 kg whose height is 1.3 m. Use a linear approximation to estimate the boy's BMI if (W, H) changes to (36, 1.32).