The cumulative distribution function of a discrete random variable $X$ is

$X$	$1$	$2$	$3$	$4$	$5$	$6$
$F\left(X\right)$	$0·18$	$0·43$	$0·54$	$0·68$	$0·89$	$1·00$

Then, $P(1<X<5)=$

The following table represents a probability distribution for a random variable $X$ :

Then, the value of $k$ is

If the probability density function of a random variable $X$ is

$f\left(x\right)=\left\{\begin{array}{cc}0.5x,& 0\le x\le 2\\ 0,& \mathrm{otherwise} \end{array}\right.$

then the value of $P(0.5\le X\le 1.5)$ is

What is the mean of a random variable $X$ with probability distribution as follows:

A discrete random variable $X$ has the following probability distribution

The value of $C$ and the mean of the distribution are

$f\left(x\right)=\left\{\begin{array}{cc}k{x}^2,& 0\le x\le 2\\ 0,& \text{otherwise} \end{array}\right.$ is a probability density function of a continuous random variable $X$. The value of $k$ is