Kate spent a total of $15.45 on a trip to the movies. she spent $5.00 on a bus fares to and from the movies and $3.95 on snacks. how much did she spend on her movie ticket?

The? half-life of a radioactive substance is 20 years. if you start with some amount of this? substance, what fraction will remain in 120 ? years

I’m really confused and need to learn this

Monthly water bills for a city have a mean of $108.43 and a standard deviation of $36.98. find the probability that a randomly selected bill will have an amount greater than $173, which the city believes might indicate that someone is wasting water. would a bill that size be considered unusual?