You know that balloons must be kept away from sharp objects. They also needed to be kept away from flames. A fire can weaken the rubber and cause it to break. However, in this experiment you will find out how you can hold a balloon directly in a flame without breaking the balloon.

    Materials needed:

● two round balloons not inflated(充气的)

● several matches

● water

    Inflate one of the balloons and tie it. Place 1/4 cup of water in the other balloon, and then inflate it and tie it. Light a match and hold it under the first balloon. Allow the flame to touch the balloon. What happens? The balloon breaks, perhaps even before the flame touches it. Light another match. Hold it directly under the water in the second balloon. Allow the flame to touch the balloon. What happens to this balloon? It doesn't break.

    Why does the balloon with no water break in the flame? The flame heats the rubber of both balloons. The rubber of the balloon without water becomes so hot that it becomes too weak to resist the pressure of the air inside the balloon. However, when the balloon with water in it is placed in the flame, the water takes in most of the heat from the flame. Then, the rubber of the balloon doesn't become very hot, it doesn't weaken, and the balloon doesn't break.

    Water is a particularly good absorber(吸收者) of heat. It takes a lot of heat to change the temperature of water. On the other hand, when water cools, it gives off a great deal of heat. That's why areas near oceans or other large bodies of water don't get as cold in winter as areas at the same latitude(纬度) further inland.

    I climbed Kilimanjaro with Lava Expeditions (探险队) during the rainy season.

    I flew to Nairobi in Kenya and spent several days there. At my hotel in Nairobi I met the rest of the group with whom I would spend the next week. We all travelled on the bus together for a 6-hour journey into Tanzania and then Arusha, a quiet town.

    After we arrived at our hotel in Arusha, we had dinner and a few drinks. Then we were introduced to more members including Taddeus Minja, the main guide, who was very experienced — climbing Kilimanjaro runs through the generations (代) of his family.

    The next day the Lava Expeditions members checked if we had the correct and enough clothing for our expedition on Kilimanjaro. Only one person needed to bring more clothes.

    After that we set off, walking in the rain through the beauty of the rainforest, all the way to the first camp. I was happy the next few days as the view was so wonderful and changed every day. I suffered a little during the trip and I felt so tired. But the members of Lava Expeditions provided me with lots of encouragement, which was one of the best memories. Finally we reached the top of Kilimanjaro in bright blue skies.

I felt excited about climbing Kilimanjaro and the feeling didn't change during my trip. Lava Expeditions looked after me so well that I was deeply thankful for their help.

    Pink has never been one of the favorite colors of the fashion industry,as it's often seen as silly and not cool enough.But this spring,it's having its moment in the spotlight,all thanks to the fact that the color is no longer all about being girly and sweet.Instead,pink is taking on a new meaning of independence and power.

    This shift happened last month during the Women's March.Tens of thousands of women filled the streets of major cities in the US and in countries all around the world to protest（抗议）against the disrespect to women.What was unusual about the protests is that a lot of people taking part were wearing pink hats,making the streets appear like a "sea of pink".Even though the hats were without any slogan（标语）,their pink color is thought to have sent out a message that is louder than any words."We women have power and we're not going to sit down and shut up," Aileen Gildea,one of the protesters in the US,told The Boston Globe.

    Now young people are changing their attitudes to pink.They are no longer trying to escape pink,but give new meanings to it instead.

    "Women who came before us ...to be taken seriously they had to get away from the symbols used to make women seem less capable.Younger women don't have that reaction.They're more interested in breaking and rebuild those symbols,"Audrey Gelman,a businesswoman in the US,told The Wall Street Journal.

    So sometimes it's not the thing itself that needs to be changed,but the way we look at it.And in the case of pink, what used to be seen as silly may be turned into something really serious.

    Candace Payne's life changed forever in May 2017 when she posted a video of herself laughing crazily and wearing a mask. The video spread widely and "Mask Mom "became a household name.

    During the two years since that, Candace has published several books, starred in a TLC. web series and went on tour with Mandisa. She made appearances on late night talk shows, met J. J. Abrams and was able to fulfill a dream of taking her family to Disney World. It was a busy but joyful time.

    Her latest book is Consider It Joy. "I feel like people need a tool in their hands to actually get the joy they are fighting for, "Candace says, "The book can help you keep track of how much space and time you are devoting to things that aren't worth it in comparison to the joy that I know I could have."

    Getting joy is something that has always been important to Candace. "What the opportunity offered me was not a forced open door," Candace says, "Many people are trying desperately to push things open when they have to be obedient(顺从的) to the little things."

    Trusting herself has required being confident in saying no. She uses a simple tool to evaluate whether an opportunity is right to her. Candace says, "I have a balance beam (平衡木)where I'm asked to walk every single day as a mom, a wife, a speaker and an author. There are so many things I need to balance at a time. I have to realize what belongs there and what doesn't. The most important factor is joy."

    That's the heart behind the book Consider It Joy. "I really wanted to give people more than just advice about joy, Candace says, "I wanted to give them the ability to actually own it in their everyday life."

    In earliest times, men considered lightning to be one of the great mysteries (神秘的事物)of nature. Some ancient peoples believed that lightning and thunder were the weapons (武器) of the gods.

    In reality, lightning is a flow of electricity formed high above the earth. A single flash of lightning 1.6 kilometres long has enough electricity to light one million light bulbs (灯泡).

    The American scientist and statesman, Benjamin Franklin, was the first to show the connection between electricity and lightning in 1752. In the same year he also built the first lightning rod (避雷针). This device (装置物) protects buildings from being damaged by lightning.

    Modern science has discovered that one stroke (闪击) of lightning has a voltage (电压) of more than 15 million volts (伏特). A flash of lightning between a cloud and the earth may be as long as 13 kilometers, and travel at a speed of 30 million meters per second.

    Scientists judge that there are about 2,000 million flashes of lightning per year. Lightning hits the Empire State Building in New York City 30 to 48 times a year. In the United States alone it kills an average (平均数) of one person every day.

    The safest place to be in case of an electrical storm is in a closed car. Outside, one should go to low ground and not get under tress. Also, one should stay out of water and away from metal fences. Inside a house, people should avoid open doorways and windows and not touch wires or metal things.

    With lightning, it is better to be safe than sorry?

On that hot August day in 2023, as ash rained down and flames closed in, Jim Rhodes didn't want to be anywhere but Coulterville. "My kid called from Alabama. We first heard ·about the fire from him," Rhodes recalls. "He said, ‘Evacuate（撤离）!'I said, ‘Evacuate? To where?'"

Coulterville is a tiny town located among dry hills where local people raise cattle and other livestock. It has a main street, a park and a museum. It's got a cafe, a grocery shop and a post. And with summer temperatures routinely topping 100 degrees, it has fires—sometimes big fires.

Eventually, this big fire got a name: the Moc Fire, for the tiny town of Moccasin-where it began as a brush fire.

It burnt for 10 days, consuming almost 3,000 acres.

Rhodes woke to find his truck covered in ashand the news was broadcasting evacuation orders. Ranchers（牧场主） across the region were fighting to protect their animals, loading them into the truck or just setting them loose to find safety. Volunteers were readying fairgrounds nearby to shelter animals. Already they were filling up with dogs, cats, chickens, horses, cattle, goats, sheep and rabbits.

As residents and animals were brought out, firefighters poured in. "With them came the biggest bulldozer（挖土机）I've ever seen," says Rhodes. "And they were sent to cut the firebreak that could save the town. We knew that if it made the cut, we'd all have to get out of here."

The situation was clear. The danger was growing. But slowly Rhodes realized that he hadn't come to Coulterville just to leave when the town needed him. He stayed, joining the handful of residents who gathered around the main street where fire officials posted updates. He knew he could help somebody, somehow.

Around midmorning, a farmer he'd never met came by asking for help with animal evacuation. Rhodes's phone was still ringing, but he knew what to do. "I hung up my phone, got in the truck and headed down to his farm," he says.