It's D, because the mean doesn't matter as much if it's only taken in a small variability. The mean was selected from 25 random pages in the book, that is why it is right.
The answer to this question is A. 120°
Given.
Radius of the Half sphere is 3 inches.
From the figure;
Radius of half sphere= Radius of cylinder= Radius of cone=3inches
Height of cone= 4inches.
Height of cylinder=6inches.
Volume of cone=(πr²h)/3
=(π3²×4)/3
=(12π) inch³
volume of cylinder= πr²h=π3²6=54π inch³
Volume of half sphere= (4/3) π r³=π(4×3³)/3 (1/2)=π×4×9/2=18π inch³
Total area of Composite figure=(12π +54π +18π) inch³
=84π inch³
=(84)× 22/7inch³
=12×22 inch³
=264inch³
Hope it helps...
Regards;
Leukonov/Olegion.