At the dentist's office, Serge is getting a cavity filled. His insurance will pay for 80% of the cost of the filling. If the filling costs $130, about how much will his insurance pay?
Use estimation.
А: $75
B: $80
с: $100
D: $210

The magnitude, m, of an earthquake is defined to be m=log l/s, where i is the intensity of the earthquake (measured by the amplitude of the seismograph wave) and s is the intensity of a “standard” earthquake, which is barely detectable. what is the magnitude of an earthquake that is 1,000 times more intense than a standard earthquake? use a calculator. round your answer to the nearest tenth.

Janet drove 300 miles in 4.5 hours. write an equation to find the rate at which she was traveling

For what value of (y) is 3^3/3^y =1/9