A manufacturing firm has received a contract to assemble $1000$ units of test equipment in the next year. The firm must decide how to organize its assembly operation.

a$)$ Skilled workers, at $$33$ per hour each, can individually assemble the test equipment in $2\mathrm{.}6$ hours per unit.

b$)$ Teams of $4$ less skilled workers, at $$19$ per hour each, can assemble a unit in one hour.

The approach that is more economical is

i$)$ a

ii$)b$

iii$)$ both a and $b$ are equal in cost

iv$)$ not enough information is given to decide