How are electromagnetic waves different than all other waves?

Need people build a dam to create a reservoir that supplies water a nearby city needs. describe two ways this action will likely affect the water cycle in the local environment. (5 points) worth 20 points

The number of passengers who arrive at the platform of a subway station for the 10 am train is a random variable with a mean of 120 and a variance of 16. find the lower bound of the probability that there will be between 100 and 140 passengers (round off to second decimal place).

What was the first instrument to ever record an earthquake?