Questions

'Rare earth'(They are all metals)

Two series alternate here, with every third number following a different pattern.
In the main series, 4 is added to each number to arrive the next.
In alternate series, 5 is subtracted from each number t arrive the next number.
Here in the main series 
3 + 4 = 7
7 + 4 = 11
11 + 4 = 15
15 + 4 = 19

In alternate series 
24 - 5 = 19
19 - 5 = 14...

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

The first bank established in India in the year 1770 was Bank of Hindustan followed by the General Bank of India in the year 1786. The State Bank of India (SBI) was the still existing oldest bank which was established in the year 1806 in the name of Bank of Calcutta.

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.