题目

在一个密闭的容器内有甲、乙、丙、丁四种物质，在一定条件下反应一段时间，测得反应前后各物质的质量如表所示： 物质甲乙丙丁 反应前质量（g）4104044 反应后质量（g）22待测5610 下列说法错误的是（ ） A．该反应为分解反应B．甲、丙变化的质量比为9：8C．乙可能是该反应的催化剂D．反应后乙的质量为0 gStudents from Florida International University in Miami walked on water Thursday for a class assignment. To do it，they wore aquatic (水上的)shoes they designed and created.Alex Quinones was the first to make it to the other side of a 175－foot lake on campus in record time—just over a minute. Quinones，who wore oversized boat－like shoes，also won last year and will receive $ 500.Students had to wear the aquatic shoes and make it across the lake in order to earn an “A” on the assignment for Architecture Professor Jaime Canaves'Materials and Methods Construction Class.“It's traditional in a school of architecture to do boats out of cardboard for a boat race. I thought our students were a little bit more special than that，” Canaves said.“We decided to do the walk on water event to take it to the next level.”A total of 79 students competed in the race this year in 41 teams. Only 10 teams failed to cross the lake. Others who fell got back up and made it to the end. The race is open to all students and anyone in the community. The youngest person to ever participate was a 9－year－old girl who competed in place of her mother，while the oldest was a 67－year－old female.A large crowd on campus joined Canaves as he cheered on the racers. He shouted encouraging words，but also laughed as some unsteadily made their way to the end.“A part of this is for them to have more understanding of designing and make it work better，” he said. It is also a lesson in life for the students.“Anything，including walking on water，is possible，if you do the research，test it and go through the design process seriously.【1】Which statement about Alex Quinones is true ?A. He finished the race in less than a minute.B. He won the race with the help of 2 boats.C. He failed the race last year.D. He set a new record this year.【2】For what purpose did the students take part in the race?A. To go across the lake to school.B. To test their balance on the water.C. To pass Professor Canaves' class.D. To win the prize money of $ 500.【3】Which of the following is true about the race?A. The students who fell into the water had to quit.B. More than 20 teams failed to cross the lake.C. The students kept silent when the other racers competed.D. The youngest competitor competed instead of her mother.【4】According to Canaves，this race can help the students .A. understand designing betterB. achieve almost everythingC. work together and unite as oneD. walk on the surface of water