Grasslands are found in most ecoregions of the Earth.

For example, there are five terrestrial ecoregion classifications of the temperate grasslands, savannas, and shrublands ecosystem, which is one of eight terrestrial ecozones of the Earth's surface.

Open market operations (OMO) refer to the buying and selling of government securities in the open market in order to expand or contract the amount of money in the banking system.

The s,p,d,f configuration for cobalt (Co) is 1s22s22p63s23p64s23d7, determined by the position of the element on the periodic table. The electron configuration for Cobalt at ground state would simply be Co: [Ar] 4s²3d⁷.

The electron configuration of Cobalt will end in d block as Cobalt is an inner transition metal. Cobalt is in the 7th column of the d block and therefore has 7 d electrons d7.

A modem is nothing but short for Modulator and Demodulator. It is used mostly for connecting to the internet.

A modem is a device or program that enables a computer to transmit data over, for example, telephone or cable lines. Computer information is stored digitally, whereas information transmitted over telephone lines is transmitted in the form of analog waves.

The given number series is 

3, 5, 8, 15, 28, 51, ?

Here the pattern it follows is

3

3 + 2 = 5 ( add prime number less than 3 i.e, 2)

5 + 3 = 8 (3 is prime number less than 5)

8 + 7 = 15 (7 is prime number less than 8)

15 + 13 = 28 (13 is prime number less than 15)

28 + 23 = 51 (23 is prime number less than 28)

51 + 47 = 98 (47 is prime number less than 51)

Hence, the next number in the given number series is 98.

The day of the week repeats every 7 days.

Given today is Friday. Again Friday is repeated on the 7th day, 14th,... on 7 multiple days.

Hence, Friday is on the 63rd day, as 63 is multiple of 7.

Now, the required day of the week on the 65th day is Sunday.

The first written story that has come down to us is The Epic of Gilgamesh.

It is a mythologized account of a historical figure, Gilgamesh, a ruler of the Sumerian city-state of Uruk, believed to have ruled sometime between 2700-2500 BC.

Some more NPP Acronym stands for 

NPP New Patriotic Party

NPP Nuclear Power Plant

NPP Notice of Privacy Practices

NPP Non-Physician Practitioner

NPP New Progressive Party

NPP National Patriotic Party

NPP Notice of Proposed Procurement

NPP Neighbourhood Police Post (Singapore)

NPP Non-Paged Pool (memory)

NPP Nurse Practitioner in Psychiatry.