Moods,say the experts,are feelings that are likely to become fixed,having effects on one′s outlook（way of looking at things）for hours,days or even weeks.That′s great if your mood is a pleasant one,but a problem if you are sad,anxious,angry or simply lonely.
Perhaps the best way to deal with such moods is to talk them out;sometimes,though,there is no one to listen.Modern pharmacology（药物学）offers a lot tranquilizers（镇定剂）and anti-anxiety drugs.What many people don′t realize,however,is that scientists have discovered the effectiveness of several non-drug methods to make you free from an unwanted mood.These can be just as useful as drugs,and have the added benefit of being nonpoisonous.So next time you feel out of sorts,don′t head for the drug store--try the following method.
Of all the mood-changing self-help techniques,aerobic exercise seems to be the best cure for a bad mood."If you could keep the exercise,you′d be in high spirits,"says Kathryn Lance,author of Running for Health and Beauty.
Researchers have explained biochemical and various other changes that make exercise compare favorably to drugs as mood-raiser.Physical work such as housework,however,does little.The key is aerobic exercise--running,cycling,walking,swimming,or other repetitive and sustained activities that increase the heart rate and circulation（循环）,and improve the body′s use of oxygen.Do them for at least 20 minutes a time,three to five times a week.
It can be inferred from the passage that
考情点拨：推理判断题。应试指导：文章第二段说，科学家们发现．非药物方法可像药物一样改变人们的心情，而且无毒副作用。言外之意，药物具有毒副作用：
把10gMgCl2和MgSO4的混合物溶于适量水中，滴加2mol／L的BaCl2溶液至沉淀完全，共消耗BaCl2溶液25mL。求混合物中MgCl2和MgSO4的质量各是多少克
固定在匀强磁场中的正方形导线框abcd，各边长为1．其中ab是一段电阻为R的均匀电阻丝，其余3边均为电阻可忽略的铜线。磁场的磁感应强度为B，方向垂直纸面向里。现有一与ab段的材料、粗细、长度都相同的电阻丝PQ架在导体框上，如图所示。PQ以恒定速度方向如何
一小物块以速度v0=10m／s沿光滑地面滑行，然后沿光滑曲面上升到顶部水平的高台上，并由高台上飞出，如图所示。问当高台的高度h多大时，小物块飞行的水平距离最大这个距离是多少(g=10m／s2)
某晶体盐的水溶液呈浅绿色，在此溶液中通入氯气，溶液变为棕黄色，把所得棕黄色溶液分成两份：一份加入KSCN溶液，溶液变深红色；另一份加入BaCl2溶液，产生不溶于稀HNO3的白色沉淀，则该晶体盐的化学式是_______。
欲除去乙烷中的乙烯，可将混合气体通过盛有_______的洗气瓶；欲除去乙炔中的硫化氢，可将混合气体通过盛有_______的洗气瓶。
浓硝酸常盛装在棕色瓶中，且贮放在冷暗处，原因是_______，
碳酸氢钠溶液和烧碱溶液反应的离子方程式为_______。
常温下，氨水中存在的离子有_______。
在酸或碱存在的条件下，甲酸甲酯跟水发生水解反应的化学方程式为_______。
有下列几种气体：H2、O2、HCl、NO、NH3、CH4，其中通常情况下能用来和水做“喷泉”实验的是_______。
