Rebecca stops after reading two or three paragraphs in her psychology text. She rehearses and thinks about the material she has just read before continuing on. The aspect of memory Rebecca is most concerned with is the limited duration of. A) sensory memory.
B) short-term memory.
C) iconic memory.
D) echoic memory.

(B) Short-term memory

Explanation:

 The short-term memory is one of the type of primary memory and the capacity of the short term memory is less as it is able to hold small amount of the data.

The information are available for the short duration and the data or any type of message are temporary stored in our memory.

According to the given question, the Rebecca is concerning with the short term memory as it sustain for the limited time or duration in the memory. Therefore, Option (B) is correct answer.    

marginal cost is a microeconomic measure that us to evaluate the extent to which the level of production of a good is sustainable in accounting, that is, to how many quantities the company plans to profit from the production of the good.

the concept of marginal cost is simple, it means the cost of producing one more item. for example, in the case of pies, the marginal cost is the cost of producing one more pie than those that have already been produced.

it is important to understand that productive activity influences marginal cost. the marginal cost of some goods can be very high, while others may be insignificant. for example, the marginal cost of producing an extra plane is very high. already the marginal cost of a water company to provide 1l more water is derisory.

in the case of pies, the cost involves the inputs, the labor and the fixed cost, which involves the fixed space of the bakery. the level of production initially has the marginal cost decreasing because there is space and manpower available. however, to produce more you have to hire more workers and buy more inputs. if physical space is limited, workers will conflict with places, inputs and their productivity will decrease, meaning there is an optimum point of production for each level of space and manpower. from this point on, the productivity of the workers will be getting smaller because of lack of space, so that the marginal cost of producing one more pie will be increasing. so, although you have not posted the chart, but if you have the answer, you can see that my explanation goes according to the marginal cost curve that will increase from the 4th pie, answer (c).