In europe, gasoline efficiency is measured in km/l. if your car's gas mileage is 31.0mi/gal , how many liters of gasoline would you need to buy to complete a 142-km trip in europe? use the following conversions: 1km=0.6214mi and 1gal=3.78l.

Twenty-five percent of the customers entering a grocery store between 5 p.m. and 7 p.m. use an express checkout. consider five randomly selected customers, and let x denote the number among the five who use the express checkout.

Carla was trying to decide what to do saturday evening. she has $100 available to spend for the evening. she has narrowed her choices down to these events: braves game, a concert of an artist she likes, or the georgia aquarium. admission to the braves game is $25, hot dogs cost $10, sodas cost $5. the concert costs $25 for admission, $20 for a souvernir t-shirt, and $10 for a soda. the georgia aquarium has the show of a lifetime with an all you can eat and drink that costs $100. carla does not want to take any driving chances, so in addition to the cost of the aquarium, she will also need to pay for her uber/lyft, which is $15 each way. which option should carla choose if she wants to spend the least? based on that choice, what then is carla's oppotunity cost? fully explain your answer in at least one paragraph.

Alistair has 5 half-pounds chocalate bars. it takes 1 1/2 pounds of chocalate,broken into chunks, to make a batch of cookies. how many batches can alistair mke with chocalate he has on his hand?