What is the place value of the 8 in 384,321?

In the presence of supragingival dental biofilms, a subgingival microbiota contains

A) > 10% motile rods. B) > 5% spirochetes. C) < 2% Gram-positive bacteria. D) < 10% Gram-negative bacteria.

The following is noted on an ECG during exercise electrocardiography. What is this feature called? 

A. ST segment elevation B. ST segment depression C. PVC D. Wide QRS duration