A colorimeter is an instrument used for chemical analysis by comparing a liquid’s color with standard colors. In an experiment, a scientist used two colorimeters and noted the readings. The first colorimeter showed consistent readings that were five points lower than the actual reading. The second colorimeter provided readings that were the same as the actual reading. Which two statements are implications of these readings? 1). The first colorimeter is reliable but not valid.

2). The second colorimeter is valid and reliable.

3). Both the colorimeters are reliable and valid.

4). The readings of the first colorimeter can be used without repeating the experiment.

5). The readings of the second colorimeter aren’t reliable and can’t be used for the experiment.

The correct answers are option A and B

Explanation:

The first colorimeter is reliable because the the reading it is showing is same for all the times the experiment is done. Though the result obtained is wrong but it is reliable.

The second colorimeter is valid and reliable because it is showing the correct results again and again. This is valid result as it is giving the result same as that of actual readings.

stress fractures occur largely in the feet and legs and are common in sports that require repetitive impact, primarily running/jumping sports such as gymnastics or track and field.

white blood cells or wbc s are mainly 2 types-

1.agranulocytes

2.granulocytes

the monocytes or macrophages of agranulocytes , dendritic cells which are accessory leucocytes, and b cells which is one type of lymphocytes   identify the antigens present on the pathogen's surface. these three cells are called antigen presenting cells(apc) which are phagocytes and destroy the antigens by secreting antitoxins. besides this leukocyte is always plays vital role in the immunity of the body.