This illustration shows how light enters a reflector telescope. Optical telescopes allow us to see further; they are able to collect and focus more light from distant objects than our eyes can alone. This is achieved by refracting or reflecting the light using lenses or mirrors.
Labor burden is the actual cost of a company to have an employee, aside from the salary the employee earns. Labor burden costs include benefits that a company must, or chooses to, pay for employees included on their payroll.
labour noun (WORK) C1 [ U ] practical work, especially when it involves hard physical effort: The car parts themselves are not expensive, it's the labour that costs the money. manual labour (= hard work using the hands) C1 [ U ] workers, especially people who do practical work with their hands: skilled/unskilled labour.