Answer:
575in³
Step-by-step explanation:
Volume for a Sphere = 4/3πr³
Radius = 13/2 = 6.5
4/3(3.14)(6.5³) = 1149.763333
Because it's half a sphere, just divide by 2
1149.763333/2 = 574.881667
Rounded to the nearest cubic inch = 575
9-12 is -3
20 inches
It is because QS and PN are congruent.