You are a helpful assistant. When the user asks a question, your response must include two parts: first, the reasoning process enclosed in <think>...</think> tags, then the final answer enclosed in <answer>...</answer> tags.Please provide a clear, concise response within <answer> </answer> tags that directly addresses the question.
system
<image>Figure shows a 1000-kg mass being lowered by a cable at a uniform rate of 4 m/s from a drum of 550-mm-diameter weighing 2.5 kN and having a 250-mm-radius of gyration.(a) What is the kinetic energy in the system?(b) The uniform rate of descent is maintained by a brake on the drum which applies a torque of 2698 N⋅m. What additional brake torque is required to bring the system to rest in 0.60 s?<image 1>
A. 9673J,2218N⋅m
B. 5723J,1218N⋅m
C. 9673J,1218N⋅m
D. 5723J,2218N⋅m

Please answer the question with option letter from given choices in the format of Answer: <option letter>. You FIRST think about the reasoning process as an internal monologue and then provide the final answer. The reasoning process MUST BE enclosed within <think> </think> tags. Please answer the final answer within the <answer> </answer> tags.
user
A
Figure shows a 1000-kg mass being lowered by a cable at a uniform rate of 4 m/s from a drum of 550-mm-diameter weighing 2.5 kN and having a 250-mm-radius of gyration.(a) What is the kinetic energy in the system?(b) The uniform rate of descent is maintained by a brake on the drum which applies a torque of 2698 N⋅m. What additional brake torque is required to bring the system to rest in 0.60 s?<image 1>
A. 9673J,2218N⋅m
B. 5723J,1218N⋅m
C. 9673J,1218N⋅m
D. 5723J,2218N⋅m

Please answer the question with option letter from given choices in the format of Answer: <option letter>. You FIRST think about the reasoning process as an internal monologue and then provide the final answer. The reasoning process MUST BE enclosed within <think> </think> tags. Please answer the final answer within the <answer> </answer> tags.
val