The specialized sites that are contacts between cardiac muscle cells are called what?

The maximum pressure reached during an explosion may be more than ___ times greater than atmospheric pressure

A) four B) six C) eight D) ten

Which of the following is not a common symptom of Klinefelter's syndrome?

A) abnormally heavy body hair B) failure of the penis and testicles to mature fully C) mental retardation D) breast enlargement