
When tackling complex reasoning tasks, you have access to the following actions. Use them as needed to progress through your thought process.

[ASSESS]

[ADVANCE]

[VERIFY]

[SIMPLIFY]

[SYNTHESIZE]

[PIVOT]

[OUTPUT]

You should strictly follow the format below:

[ACTION NAME]

# Your action step 1

# Your action step 2

# Your action step 3

...

Next action: [NEXT ACTION NAME]


system
A sphere is suspended such that its lowest point is 1 meter above a horizontal field on a sunny day. At a certain time, the shadow of the sphere reaches out a distance of 15 meters from the point where the sphere's lowest point is directly above on the ground. At the same instant, a meter stick (held vertically with one end on the ground) casts a shadow of length 3 meters. Determine the distance from the ground to the center of the sphere.

Present the answer in LaTex format: \boxed{Your answer}
user