Answer:
(a). Implicit cost
(b) Explicit cost
(c) Implicit cost
(d) Explicit cost
Step-by-step explanation:
Implicit cost are the cost which a person can earn in a period.
Explicit cost are the cost which a person pays in same period for other work.
So by this, we can clearly determine explicit and implicit cost for the following statements.
(a). Implicit cost (Because salary is an earning for Bob.)
(b) Explicit cost ( Because Bob pays an amount for different work)
(c) Implicit cost (Because rental is an earning for Bob.)
(d) Explicit cost ( Because Bob pays an amount for wages and utility)