Answer:
B
Step-by-step explanation:
If the diameter of sphere B is 42, that means the radius is half, so it is 21.
The question is asking what multiplied by 24 is 21, or 21 divided by 24. 21/24 can be simplified to 7/8.
Answer:

Step-by-step explanation:
Look at the picture.
ΔADC and ΔCDB are similar. Therefore the sides are in proportion:

We have

Substitute:
<em>cross multiply</em>


For x use the Pythagorean theorem:

I think it is D
Hope my answer help you?