In a factory, there are 1000 workers consisting of 400 white colour workers and 600 blue colour workers. In white colour workers, 300 are male workers; and in blue colour workers, only 200 are male workers. How many female workers are there in the factory?

A. The central limit theorem B. The law of statistical regularly C. The law of inertia of large numbers D. None of the above

A. Sampling error B. Measurement error C. Coverage error D. Non-response error

A. Both (A) and (R) are true B. (A) is true, but (R) is false C. (A) is false, but (R) is true D. Both (A) and (R) are false

A. 0 B. 1 C. 0.4 D. 0.8