A game of chance consists of spinning an arrow which is equally likely to come to rest pointing to one of the number $1,2,3,........,12$ as shown in figure.
What is the probability that it will point to multiple of $4$ ?

The mean deviation about the mean of the following data is?

The standard deviation of the data 6, 5, 9, 13, 12, 8, 10 is

The median and S.D of a distribution are 20 and 4 respectively. If each item is increased by 2, the new median are S.D are:

If marks scored by students of class are $1, 2, 4, .....2^{10}$ with frequency $1, 2, 3, 4 .....11$ then median is