The probability of the event 'the sun rises in the east' is .............

Bulbs are packed in cartons,each containing $40$ bulbs. Seven hundred cartons were examined for defective bulbs,and the results are given in the following table:

Number of defective bulbs	$0$	$1$	$2$	$3$	$4$	$5$	$6$	more than $6$
Frequency	$400$	$180$	$48$	$41$	$18$	$8$	$3$	$2$

One carton was selected at random. What is the probability that it has less than $4$ defective bulbs?

The probability of a certain event is ........

$A$ box contains $100$ cards marked with numbers $1$ to $100$. If one card is drawn at random from the box,find the probability that the number on the card is: $(1)$ a multiple of $7$,$(2)$ a number smaller than $30$,$(3)$ a prime number.

From the list of telephone numbers of $100$ employees of a factory, the following frequency distribution of their unit place digit (for example, in the number $25828573$, the unit place digit is $3$) is given in the table below:

Unit digit	$0$	$1$	$2$	$3$	$4$	$5$	$6$	$7$	$8$	$9$
Frequency	$8$	$9$	$12$	$15$	$10$	$7$	$12$	$10$	$9$	$8$

Find the probability that a randomly selected employee has a telephone number with unit digit $3$.

In a medical examination of students of a class,the following blood groups are recorded:

Blood group	$A, AB, B, O$
Number of students	$10, 13, 12, 5$

$A$ student is selected at random from the class. The probability that he/she has blood group $B$,is: