在一块农田里长着绿油油的小麦，影响小麦生活的环境因素包括____ 因素和____ 因素。

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Jacob's Pillow Dance Festival

Where: Becket, Massachusetts

When: June 15-Aug 24

    Each summer, this influential dance center presents a number of classes and performances by more than 50 companies from around the world. Highlights (最精彩的部分) this season include the Dance Theater of Harlem's production of Alvin Ailey's “The Lark Ascending”, which opens the festival.

    Many events are free. Ticketed performances start at $22. jacobspillow.org.

Moab Music Festival

Where: Moab, Utah

When: Aug 29-Sept 9

    This area is better known for mountain biking than for music. But since 1992, it has hosted a private festival that brings classical, jazz, Latin and other types of music to the land. This year there will be 16 concerts, including three “Grotto Concerts”, where guests take a 45-minute boat ride down the Colorado River to performances.

Events start at $25. moabmusicfest.org.

Cheyenne Frontier Days

Where: Cheyenne, Wyoming

When: July 19-28

    There's something for everyone at this 117-year-old festival, from an “Indian village” and Old West museum to country concerts. But the competition is still the main attraction, with cowboys and cowgirls competing for major money in the world's largest outdoor stage.

Competition tickets start at $18, and concert tickets at $23. cfdrodeo.com.

The Glimmerglass Festival

Where: Cooperstown, New York

When: July 6-Aug 24

    Each summer, opera lovers from around the country (and the world) travel to upstate New York to watch productions that include stars like Nathan Gunn and Ginger Costa-Jackson. This year's performances include Wagner's “The Flying Dutchman” and Verdi's “King for a Day”, in honor of the 200th birthdays of both composers (作曲家).

Tickets start at $26. glimmerglass.org.

—Yuzuru Hanyu from Japan won the first gold medal at Pyeongchang Olympics on Saturday in men's single figure skating,        Jin Boyang set Chinas best result in the event as the fourth finisher.

如图所示，两个质量均为m的完全相同的金属球壳a和b，其壳层的厚度和质量分布均匀，将它们固定于绝缘支座上，两球心间的距离l为球半径的3倍．若使它们带上等量异种电荷，使其电荷量的绝对值均为Q，那么关于a、b两球之间的万有引力F_引和库仑力F_库的表达式正确的是（   ）

    Here are some tips about how to keep healthy.

1) Healthy food is important. If you want to keep healthy, eat lots of fruit and vegetables. Don't eat much meat.

2) Water is important. Drink water every day. Milk is good for you, too. Don't drink sweet drinks.

3) Exercise is important. You can ride your bike or play soccer. Going swimming is a good idea.

4) Clean air is important. If you are free, you can go to the park and enjoy clean air.

5) Your teeth are important. You should brush your teeth twice a day.

6) Sleep is important, too. Go to bed early. Don't stay up late, or you will feel sleepy.