Answer:
a) 0.4164
Step-by-step explanation:
Mean lifespan (μ) = 18.8 days
Standard deviation (σ) = 2 days
For any given lifespan 'X', the z-score is:

For X=12.04 days:

A z-score of -3.38 falls in the 0.036-th percentile of a normal distribution.
For X=18.38 days:

A z-score of -3.38 falls in the 41.68th percentile of a normal distribution.
The probability that a butterfly lives between 12.04 and 18.38 days is

Answer:
CSA of cylinder = 704cm²
We know that
CSA of cylinder = 2πrh
or 2πrh = 704
or, 2*22/7 *8 *h = 704 ( since r=8cm)
or, 352h = 704*7
or, h = 4928/352 = 14cm