Which of the following is not a reason why stis spread so quickly?
a.
many people with stis are asymptomatic.
b.
negative stigmas prevent people from seeking .
c.
protection used during sex usually fails.
d.
many people have a false sense of invulnerability.

If you were running a marathon, which type of muscle fibers would be most useful to you? a. slow-twitch b. fast-twitch, type i a c. intermediate-twitch, type ii b d. slow-intermediate twitch, type i b select the best answer from the choices provided. a b c d