Can we see what the graph is?
(a) Using a suitable probability calculator, the probability is 0.5987.
(b) The calculation is done the same way, but the population sigma is divided by the square root of the sample size. The probability is 0.9514.
We have two rational expressions. One in numerator and one in denominator.
Dividing by a fraction is equivalent to multiplying by its reciprocal. The rational expression in the denominator can be multiplied by taking its reciprocal to simplify the overall expression as shown below.

There are no common factors, so the expression can be simplified any further.
If 5.6 and 2.1 are the measurements then:
you multiply 5.6 and 2.1 to get the area.
Area=11.76squared
You add 5.6+5.6+2.1+2.1 to get the perimeter.
Perimeter=15.4