Đốt cháy hoàn toàn x mol este e chỉ chứa este cần dùng 3,5 x mol O2 thu được a mol CO2 và b mol H2O với a trừ b = x công thức phân tử của X là

The diagram shows the positions of the sun, moon and earth during spring tides, when the high tides are at their highest and low tides at their lowest. what is it about these positions that causes these high and low tides?

Mike and mitchell decide to have a foot race. they mark off a stretch of 100 yards, and recruit cindy to work the stopwatch. after running the race and looking at the results, cindy declared that mitchell was the fastest. so how did the boys times compare?

Ais a mountain created from eruptions of lava, ash, rocks, and hot gases.