91影视

The choices to classify variables are discrete random variable, continuous random variable, or not a random variable.

A random variable is a variable thatcan be numerically expressed.

A discrete variable is a variablewhose values are finite and can be counted.

A continuous variable is a variable thatcan take infinitely many values and cannot be counted.

a.

In the provided scenario, the variable is a continuous random variable as theweight of 100 babies can take infinitely many values.

Thus, the variable is a continuous random variable.

b.

In the given scenario, the variable can not be classified as a discrete variable or a continuous random variable because thepreference of a political party cannot be numerically expressed.

Thus, the variable is not a random variable.

c.

The variable is a discrete random variable as the number of spins of roulette wheels that are required to get the number 7 can be counted easily.

Thus, the variable is a discrete random variable.

d.

The foot lengths of humans are a continuous random variable as thelength of the foot can take infinitely many values.

Thus, the variable is a continuous random variable.

e.

The variable for the provided statement is a discrete random variable as only two shoe sizes are provided, which are 8 and $8\frac{1}{2}$, which can be finite in counts.

Thus, the variable is a discrete random variable.