user: You are a structured reasoning expert tasked with solving problems step by step. 
You first think about the reasoning process in the mind and then provide the answer. The reasoning process and answer should be enclosed within <think> </think> and <answer> </answer> tags, respectively, i.e., <think> reasoning process here </think> <answer> answer here </answer>. 
Given a question and the associated knowledge graph triplets (entity, relation, entity), you are asked to answer the question with these triplets and your own knowledge. 
You can break down the original question into several sub-questions and explore the given knowledge graph to solve them step-by-step. If there are multiple possible answers, choose one as the final answer. 
After thinking, when you finally reach a conclusion, clearly state the answer within <answer> </answer> tags, i.e., <answer> answer here </answer>. 
Question: blood pressure is measured using what measuring instruments? 
Knowledge Triplets: venous pressure.noun.01, base.wordnet.synset.hypernym, blood pressure.noun.01
m.07vn7ph, base.yupgrade.user.topics, Blood pressure
blood pressure.noun.01, base.wordnet.synset.hyponymy, venous pressure.noun.01
m.09vj0k5, base.yupgrade.user.topics, Blood pressure
m.07c_t89, base.yupgrade.user.topics, Blood pressure
systolic pressure.noun.01, base.wordnet.synset.hypernym, blood pressure.noun.01
m.0cjfqdp, base.yupgrade.user.topics, Blood pressure
vital sign.noun.01, base.wordnet.synset.hyponymy, blood pressure.noun.01
m.06h_8hr, base.yupgrade.user.topics, Blood pressure
blood pressure.noun.01, base.wordnet.synset.hyponymy, systolic pressure.noun.01
m.0qqmdgz, dataworld.gardening_hint.last_referenced_by, Blood pressure
m.09sq90h, base.yupgrade.user.topics, Blood pressure
blood pressure.noun.01, base.wordnet.synset.hyponymy, diastolic pressure.noun.01
m.09vj0j7, base.yupgrade.user.topics, Blood pressure
sphygmomanometer.noun.01, base.wordnet.synset.equivalent_topic, Sphygmomanometer
m.06wft1x, base.yupgrade.user.topics, Blood pressure
Newsweek, base.yupgrade.user.topics, Blood pressure
davewiner, base.yupgrade.user.topics, Blood pressure
m.07c_tgj, base.yupgrade.user.topics, Blood pressure
arterial pressure.noun.01, base.wordnet.synset.hypernym, blood pressure.noun.01
m.075_7f9, base.yupgrade.user.topics, Blood pressure
m.07v_5h6, base.yupgrade.user.topics, Blood pressure
Blood pressure, measurement_unit.dimension.instruments, Sphygmomanometer
blood pressure.noun.01, base.wordnet.synset.hypernym, vital sign.noun.01
Ana Marie Cox, base.yupgrade.user.topics, Blood pressure
m.09vj0kt, base.yupgrade.user.topics, Blood pressure
m.09sq905, base.yupgrade.user.topics, Blood pressure
m.07c_tk8, base.yupgrade.user.topics, Blood pressure
Blood pressure, base.schemastaging.context_name.pronunciation, g.125_l6gq7
pressure.noun.01, base.wordnet.synset.hyponymy, blood pressure.noun.01
m.063r36k, base.nobelprizes.nobel_honor.subject_area, Blood pressure
diastolic pressure.noun.01, base.wordnet.synset.hypernym, blood pressure.noun.01
circulation.noun.02, base.wordnet.synset.part_meronym, blood pressure.noun.01
m.07v_6p3, base.yupgrade.user.topics, Blood pressure
blood pressure.noun.01, base.wordnet.synset.hypernym, pressure.noun.01
Sphygmomanometer, measurement_unit.measuring_instrument.dimension_measured, Blood pressure
Blood pressure, user.avh.default_domain.ellerdale_topic.ellerdale_id, 0099-8db6
m.09vj0jw, base.yupgrade.user.topics, Blood pressure
blood pressure.noun.01, base.wordnet.synset.equivalent_topic, Blood pressure
m.019h, type.permission.controls, m.0qqmdgz
Wired, base.yupgrade.user.topics, Blood pressure
m.09vj0jk, base.yupgrade.user.topics, Blood pressure
m.0qqmdgz, type.object.permission, m.019h
m.09vj0kh, base.yupgrade.user.topics, Blood pressure
blood pressure.noun.01, base.wordnet.synset.hyponymy, arterial pressure.noun.01
m.08nl04f, base.yupgrade.user.topics, Blood pressure
Blood pressure, base.nobelprizes.nobel_subject_area.nobel_awards, m.063r36k
Good Morning America, base.yupgrade.user.topics, Blood pressure
m.07y51yc, base.yupgrade.user.topics, Blood pressure
blood pressure.noun.01, base.wordnet.synset.word, m.07pc6ql

Answer: Sphygmomanometer