题干

一个 92235 U原子核在中子的轰击下发生一种可能的裂变反应,其裂变方程为 92235 U+ 01 n→X+ 3894 sr+2 01 n,则下列说法正确的是(   )

A:X是原子核中含有86个中子

B:X是原子核中含有141个核子

C:因为裂变释放能量,根据E=mc2,所以裂变后的总质量数增加

D:因为裂变释放能量,出现质量亏损,所以裂变后的总质量数减少

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A

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    Traveling for business or pleasure can easily damage your health. It's easy to fail into the trap of high caloric meals and little exercise.____

    Keep a dictionary on hand

    If you are traveling somewhere with a different language, pack a dictionary and keep it close to help you negotiate(商议)the menu and make healthy food choices.____Look up the words that you don't understand to help you learn about cooking methods and ingredients(材料)so that you can choose healthy food.

    ____

    The more you can research before your trip, the easier it will be to keep a healthy lifestyle while traveling. To stay on track with your food, try to find a nearby grocery store or healthy food store, look up a couple of well rated restaurants that offer some healthy choices, and try to stay somewhere with a fridge or kitchen.

    Walk every day.

    Exploring your destination(目的地)on foot is an amazing way to take some exercise while traveling. Walk through the nature to enjoy its beautiful scenery, listen to the sound of nature and take some wonderful pictures.____

    Rent a bike.

    Cover more ground while burning calories by renting a bike. Many major cities have bike-sharing programs, or you could contact a local bike store to ask about bike rentals.____If you have an open schedule, you could even research bike tours, which are a great way to cover a long distance in a short period of time.

A. Avoid junk food and deep fried food.

B. Research the food and store some upon arrival.

C. Take a bike map of the city, research day trips and get exploring.

D. If you are exercising while traveling, make sure to take in extra water.

E. Here are some healthy travel tips which will keep you in good health.

F. You can't avoid deep fried food if you don't know that they're in there!

G. This is also a great way to find hidden attractions that aren't in the travel guides.