Nick used the calculations below to find the product od the given fractions?
(3/5) (4/9) (- 1/2)

step 1: (3) (4) (-1) / (5) (9) (-2)

step 2: (-12) / (-90)

step 3: 12/90

step 4: 2/15

in which step did his error occur?
o step 1
o step 2
o step 3
o step 4