题干

2017年11月10日,素有“中华神盾”美誉的151郑州号(如图所示)从浙江舟山起航,赴泰国参加东盟成立50周年国际舰队检阅活动。当士兵登上“郑州”号时,“郑州”号所受的浮力____(选填“变大”“变小”或“不变”),当舰底某位置距海面3m时,该位置受到海水的压强为____Pa。(海水的密度为1.03×103kg/m3,g取10N/kg)

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答案(点此获取答案解析)

变大,3.09×104

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   Height is just one of the thousands of features your genes decide. In fact, because you have two parents, your genes provide you a height that usually lands somewhere between the height of each parent. If both your parents are tall, then most probably you will be tall, too, but if you have questions about how tall you're going to be, ask your doctor if he or she can help you find it out.
    But genes don't decide everything. For example, eating an unhealthy diet can keep you from growing to your full potential(潜力). Getting plenty of sleep and enough exercise will help you grow to the expected height.
    No doubt you're wondering how fast you should grow. It depends. There's no perfect or right answer. Generally speaking, kids grow about 2 inches (6 centimeters) a year between age 3 and the time when they start puberty (when your body starts changing and becoming more grown up).
    Your doctor will know how your growth has been going over the years. Two centimeters here and 2 inches there are not nearly as important as the height you're at now, how you've been growing up to this point, and what other changes your body may be going through.
    Don't be scared if you seem to have grown a lot in a very short time. Everyone has a growth spurt(高峰)during puberty. The age for starting puberty is about 10 for girls and about 11 for boys. But it can be earlier or later ----between 7 and 13 for girls and 9 and 15 for boys.
    You'll usually begin to notice that you're growing faster about a year or so after your body starts to show the first changes of puberty.