Answer:
Proportion of the trees will have diameters between 2 and 6 inches = 0.8164
Step-by-step explanation:
Given -
Mean
= 4
Standard deviation
= 1.5
Let X be the diameter of tree
proportion of the trees will have diameters between 2 and 6 inches =
= 
=
Put [
]
= 
= 
= .9082 - .0918
= 0.8164
Mass of freight train: 9.98 • 106
= 1057.88 kg
mass of aircraft carrier: 7.3 • 107
= 781.1 kg
difference: 1057.88 - 781.1
= 276.78 kg
= 2.7678 x 10^2