Need help. I cant understand this one.

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

In which form is the following function written? y = - 2(x – 3)(x + 5)

V=x^4-y^4 pick three expressions that can represent the three dimensions of the prism (each in meters)