Identify the each statement below as either true or false.

$1.$ Cost per unit is computed by combining costs per unit across separate processes$\mathrm{.}2.$ Service companies cannot use process costing$\mathrm{.}3.$ Costs per job are computed in both job order and process costing systems$\mathrm{.}4.$ Both job order and process operations combine materials, labor, and overhead in producing products.