Pharmaceutical companies prefers experimental studies to conducting surveys and observational studies because companies can manipulate or suggest methods easily to have good outcomes and they are able to directly observe the results. Experimental studies is a type of study in which a procedure and method is intentionally introduced.
Answer:
1
Step-by-step explanation:
Using the trigonometric identities
tan(90 - x) = cotx , cotx = 
Given
tan1tan2tan3....................... tan87tan88tan89
= tan1tan2tan3............... tan(90-3)tan(90-2)(tan90 - 1)
= tan1tan2tan3.............. cot3cot2cot1
= tan1cot1tan2cot2tan3cot3 ........................
= 1 × 1 × 1 ×....................... × 1
= 1
Answer:
d=1.4
Step-by-step explanation:
cuz 10-1.4=8.6