I finished sorting them out, if any of them are wrong pls tell me the letter (No link and don’t solve them)

Asilkworm winds its cocoon out of one long silk fiber. to make silk thread, 3 to 10 of these silk fibers are unwound from their cocoons and combined into aa single thread with a typical length of 300 yards. choose a reasonable number of silk fibers in a thread write an equation to find the total length of the silk fibersused in 300 yards of the thread

Acertain standardized? test's math scores have a? bell-shaped distribution with a mean of 520 and a standard deviation of 105. complete parts? (a) through? (c)

Evaluate-27 ^4/3/8 a) - 81/16 b) 81/16 c) 16/81