Qualitative data gives the information of quality which can not be measured in numbers. For example: Color of eyes, softness of skin.
Quantitative data is information of quantity that can be represented in numbers. For example length and mass of any object.
Zinc is a silver-gray metal is a qualitative data, here silver gray color is quality of zinc metal which can not be measured in numbers.
Chlorine has a density of 3.2 g/L is a quantitative data. The value of density can be compared with other elements by comparing the numbers.
Gallium is not found in nature is neither qualitative nor quantitative.
Nitrogen has a melting point of –210.00 °C is a quantitative data because this is expressed in numbers.
Aluminum is a solid is a qualitative data because it tells about the state of element which can not be measured in numbers.
Answer:

Given:
Radius of curvature (R) of a spherical mirror = 20
To Find:
Focal length (f)
Explanation:
Formula:

Substituting value of R in the equation:



Answer:
a) 1.2*10^{-3}cos(1.25t)
b) 0.49mV
Explanation:
a) The coil rotates periodically with period T. Hence, we can write the variation of the magnetic flux with a sinusoidal function, and with max flux NAB. Thus, we have that:

where we have used the values given by the information of the problem for N B and A.
b)
the emf is given by:

hope this helps!!