Answer: 6
Step-by-step explanation:
Answer:
a and b are positive
Step-by-step explanation:
We are given that


We have to find that a and b are positive or negative.
We have

It means b is positive and greater than 4.

Adding 3 on both sides



Hence, a is positive and greater than 4.
Therefore, a and b are positive
For this case we first write the equation of which we will use:
I (db) = 10log (l / l)
We substitute the value of l.
We have then:
l = 10 ^ 8lo
Substituting in the given equation:
I (db) = 10log ((10 ^ 8lo) / lo)
Rewriting:
I (db) = 10 * log (10 ^ 8)
I (db) = 80
Answer:
I (db) = 80
option 4