You have to actually count all the balls in the pyramid.
Simple way is to count the balls in each level.

So lower most level lets say 1st level has 4 x 4 balls; i.e. 16 balls
Similarly 2nd level has 3 x 3 balls; i.e. 9 balls.
3rd level has 2 x 2 balls; i.e. 4 balls.
The top most level has just 1 ball.

So the total number of balls is 16+9+4+1 = 30.

So the image has 30 Balls in all.

Oil from Gnetum spp a gymnosperm belonging to the family Gnetaceae is used to relieve the effects of rheumatism

The lianas and shrubs of Gnetum are found in the rain forests of the western ghats.

Except Rock color, all other Graded bedding, Ripple marks and Mud cracks are sedimentary structures.

The aim of a group or party must be

• The mission or purpose of the group - what business they are in.

• The vision or direction they are headed - often expressed as the impact they want to have distinct from their purpose. 

• The strategies for how they will get from where they are today to where they are headed; these are broadly stated, like a 50,000-foot overview, and are typically few in number, usually no more than 3-5 key areas of focus. 

• The goals and objectives for how the strategies will be implemented; these are sometimes referred to as tactics or operational plans; there is usually no specific limit on the number of these, and they are more specific and not so far out in the future, often 1-2 years or less.

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.

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.

An electric arc is a visible plasma discharge between two electrodes that is caused by electrical current ionizing gasses in the air. Electric arcs occur in nature in the form of lightning.