Answer: the z score is 2.4
Step-by-step explanation:
Since the lengths of the certain species of beetles are normally distributed, we would apply the formula for normal distribution which is expressed as
z = (x - µ)/σ
Where
x = length of the beetle species.
µ = mean length
σ = standard deviation
From the information given,
µ = 1.9 centimeters
σ = 0.2 centimeters
For a species with a length of 2.38 centimeters, the z score is
z = (2.38 - 1.9)/0.2
z = 0.48/0.2
z = 2.4