Questions

The ozone layer is a region of Earth's Stratosphere that absorbs most of the Sun's ultraviolet (UV) radiation. It contains high concentrations of ozone (O3) in relation to other parts of the atmosphere, although still small in relation to other gases in the stratosphere.

The Atmosphere is divided into 4 layers according to major changes in temperature. They are :

1. Troposphere,

2. Stratosphere,

3. Mesosphere  and

4. Thermosphere.

The farther away from earth, the thinner the atmosphere gets.

i. The 'Swachh Survekshan 2017' survey results were recently announced by Urban Development Minister M Venkaiah Naidu. The total 434 cities of India were surveyed. Indore in Madhya Pradesh is India’s cleanest city while Gonda in Uttar Pradesh is the dirtiest.

ii. Gujarat has the maximum of 12 cities among the top 50 clean cities, closely followed by Madhya Pradesh with 11 and Andhra Pradesh with eight. Uttar Pradesh accounted for half of the bottom 50 cities in the cleanliness ranking.

Top 10 clean cities of India in 2017 are:

Indore (MP)
Bhopal (MP)
Visakhapatnam (Andhra Pradesh)
Surat (Gujarat)
Mysuru (Karnataka)
Tiruchirapally (Tamil Nadu)
New Delhi Municipal Council (New Delhi)
Navi Mumbai (Mumbai)
Tirupati (Andhra Pradesh)
Vadodara (Gujarat).

Top 5 Dirtiest cities of India (with Rank) in 2017 are:

Gonda (UP)- 434,
Bhusawal (Maharashtra)- 433,
Bagaha (Bihar)- 432,
Hardoi (Uttarakhand)- 431,
Katihar (Bihar)- 430.

Stratification as actually the settling down of sediments with different properties to form layers/strata over years. Stratification especially occurs on the bed of water bodies such as oceans.

Stratified sedimentary rocks are used to study the ecological conditions over previous years/eras.  

The other choices like Windstorms, Glacial Ice and Stream water are mediums which sediments are transported.

a -  at the peak of changes in blood pressure indicates the systiolic pressure.

Mass means the amount of matter in an object. Anything that has Mass and takes up Space is called Matter.

The Study of Matter and and how matter changes is called Chemistry.

Matter has some mass and occupies some space. Space occupied by an object is called its Volume.