Sociologists define the concept of "race" as a socially constructed category composed of people who share biologically transmitted traits that members of a society consider important.

Developing a habit of wearing your lifejacket or PFD at all times also reduces the chance that you will drown should you find yourself in the water unexpectedly.

Here by observing the figure, 

we can complete the above incomplete cube with 2 cubes in 2 rows and 2 columns

=> 2 x 4 = 8.

Hence, with 8 small cubes we can complete the cube.

A Dome-shaped, muscular and membranous structure that separates as a partition of the thoracic and abdominal cavities is Diaphragm. 

Thoracic or chest cavity ::  It is the cavity where the heart and lungs are present. It is the second largest hallow space in the body.It also has vertebral column, ribs, breast bone,...

Abdominal cavity :: It is the cavity where the digestive tract, liver, kidneys, the spleen, pancreas,... are located. It is the largest hallow space of the body.

Benign prostatic hyperplasia (BPH) also called benign prostatic hypertrophy (or) prostate gland enlargement is a noncancerous enlargement of the prostate gland that can lead to lower urinary tract symptoms (LUTS).

It is the diagnosis characterized by proliferation of the cellular elements of the prostate.

Symptoms ::

As the prostate gets larger, it starts to pinch the urethra. This causes symptoms that affect your urine flow, such as:

* Dribbling when you finish

* A hard time getting started

* A weak stream, or you pee in stops and starts.

Let the initial speed of Akhil be '4p' kmph

Then speed after decrease in speed = '3p' kmph

We know that, 

Change in speed == Change in time

According to the given data,

$$\begin{gathered} 243p - 244p = 35 - 2560 \\ => p = 12 \end{gathered}$$

Hence, the initial speed of Akhil = 4p = 4 x 12 = 48 kmph.

Here to say which fraction is greater from the given options, the fraction with greater numerator with same denominator or smaller denominator with same numerator.

To find the greater fraction, among the given options, make the denominators same for the options by finding the LCM of all the denominators.

7/12, 9/16, 13/20, 32/80

Now, LCM of 12, 16, 20, 80 = 240.

Then,

140/240, 135/240, 156/240, 96/240

Here 

$$\begin{gathered} 156240 > 140240 > 135240 > 96240 \\ => 1320 > 712 > 916 > 3280 \end{gathered}$$

Hence, largest fraction = 13/20.