i. -4 x 5 = -20
ii. \(\frac{5}{7}\)(-15) + \(\frac{2}{7}\)(-15)
iii. \(-4\div(\frac{-5}{2})\)
\(-4\times\frac{-2}{5}=\frac{8}{5}\)
iv. (-1)4 x (-1)5 x (-1)2 x (-1)7
= 1 x (-1) x 1 x (-1)
= -1 x -1 = 1
v. (-2) x (-7) x 8 x (-3)
14 x 8 x -3
14 x -24 = -336.