Skip to content
Prep
Freely
Home
TOEFL
IELTS
Guides
Log in
Sign up
P
Account
Profile
My progress
Settings
Log out
TOEFL
/
Listening practice
/ Section P638
Listen to an Academic Talk
Listen to part of a talk.
Listen
25. What is the main point?
A
Reliable measurement requires understanding consistency, reference agreement, and operating conditions.
B
Calibration makes instruments permanently accurate.
C
Predictable errors cannot be corrected.
D
A small average error proves that every reading is correct.