Human activities that can increase the rate would be air from a car exhaust, large factories, and gas lawn mowers. All of these make rain more acidic which causes more chemical weathering.
The correct answer should be low to moderate intensity and long duration. For weight loss, it's better to do something at a lower intensity but for a long time than to do something quickly but pushing yourself. That's why cardio exercises and running is great for losing weight. It helps you work at your own pace and you can do them for a long time.
Bipolar disorder and depression are Mood Disorders.
This means that they are both mental health conditions that affect your mood in a chronic way, it is more than just being sad or happy. Depression is chronic (meaning long lasting), persistent, debilitating sadness/misery/despair. It creates extreme low mood. Bipolar disorder is a mixture of depression and mania. Depression would be the low mood and mania would be the exact opposite which is extreme high mood and happiness which leads to irrational and sometimes destructive behavior.