Answer:
a) 
b)
when 
Step-by-step explanation:
since y varies inversely with x.
We need to find the constant, k.
Let's use a point (x,y) on the curve.
We are given an (x,y)=(5,10):
Multiply both sides by 5:

.
So the equation is:

What is y when x=2?


Answer:
x - 2 ≥ 0
Step-by-step explanation:
The expression under the square root cannot be negative, thus
x - 2 ≥ 0 , that is
x ≥ 2
Hi, thank you for posting your question here at Brainly.
Simply substitute the value of the intensity to the variable i. Taking its logarithm to the base 10, the answer would be 7.8. Hence, 6 million ergs is equivalent to 7.8 based on the Richter scale.