观察下列等式，并回答有关问题：

$1^3+2^3=\frac{1}{4}\times 2^2\times 3^2$；

$1^3+2^3+3^3=\frac{1}{4}\times 3^2\times 4^2$；

$1^3+2^3+3^3+4^3=\frac{1}{4}\times 4^2\times 5^2$；

…

（1）若n为正整数，猜想1³+2³+3³+…+n³的值；

（2）利用上题的结论比较1³+2³+3³+…+100³与5000²的大小．

如图所示，用力F将物体紧压在竖直的墙壁上保持静止；此时增大压力F，则下列说法正确的是（　　）

1949年9月，中国人民政治协商会议第一届全体会议在北平召开，会议选举出____为主席的中央人民政府。

根据短文理解，选择正确答案。

    There are many fun, free activities that you can do as a family. All that is required is a bit of imagination and some time set aside for fun. And the best part is that these are the kind of memories a child will remember for a lifetime.

Family game night

    Find out any of the games that are already around the house. Kids often get computer games for Christmas or birthdays, and would love to have a chance to play with their family. Or, make up some games of your own. “Charades” is a fun game to play that will challenge a child to use his/her imagination. Divide the family into teams and let each team come up with words that the other has to act out.

Family art time

    Pick some time for the family to sit down and come up with their own masterpiece. It doesn't need to be just a drawing -- take some old magazines sitting around the house, let the kids cut out pictures and paste them into their own montage. Or, use items from nature. Let them use leaves, pine cones, twigs and whatever else they can find to create something from their imaginations.

Family Picnic

    Taking the family for a picnic is a great way for some fun that doesn't cost any money. If the weather is nice, take them to a park or playground and let the kids have a day of playing. Or, if it is the middle of winter and a foot of snow is on the ground, set up a picnic in the living room.

Family Field Trip

    A family field trip doesn't have to cost a dime. Ask a nearby farm if it would be alright to bring your kids out for a tour and to see some of the animals. Or take them to a park and make a scavenger hunt where they need to find certain items from nature. Ask a local business if you could bring the family for a tour to see how things work -- you might be surprised at the number of people who would be thrilled to share what they do with others, and it could be an interesting lesson for the kids.