Answer:
45% probability that a randomly selected customer saw the advertisement on the internet or on television
Step-by-step explanation:
We solve this problem building the Venn's diagram of these probabilities.
I am going to say that:
A is the probability that a customer saw the advertisement on the internet.
B is the probability that a customer saw the advertisement on television.
We have that:

In which a is the probability that a customer saw the advertisement on the internet but not on television and
is the probability that the customers saw the advertisement in both the internet and on television.
By the same logic, we have that:

12% saw it on both the internet and on television.
This means that 
20% saw it on television
This means that 
37% of customers saw the advertisement on the internet
This means that 
What is the probability that a randomly selected customer saw the advertisement on the internet or on television

45% probability that a randomly selected customer saw the advertisement on the internet or on television
The answer is 130 degrees b
The answer is I believe b=70
Answer:
50.40% probability that all 4 are different.
Step-by-step explanation:
A probability is the number of desired outcomes divided by the number of total outcomes.
Desired outcomes:
4 digits, all different
For the first digit, it can be any of them, so there are 10 possible
For the second digit, it can be any of them other than the first digit. So there are 9 possible.
For the third digit, it can be any of them, other than the first and the second. So there are 8 possible.
By the same logic, 7 possible digits for the fourth. So

Total outcomes:
4 digits, each can be any of them(10 from 0 - 9).
So

Probability:

50.40% probability that all 4 are different.