screwdriver bit set Riddles

I have a clock in my house, on the wall. On a summer's day I forgot to wind it and it stopped. Then I went to visit a friend who had a watch that was always right on time. After I stayed for a bit, I went home, made a simple alteration and set the clock just right. Now how did I do this when I had no watch on me to tell how long it took me to come back from my friend's place?

Two men were playing tennis. They played five sets and each man won three sets. How can this be possible?

Often held but never touched, always wet but never rusts, often bites but seldom bit, to use me well you must have wit. What am I?

As beautiful as the setting sun, As delicate as the morning dew; An angel’s dusting from the stars that can turn the Earth into A frosted moon. What am I?

Creatures of power, creatures of grace, Creatures of beauty, creatures of strength. As for their lives, they set everything’s pace, For all things must come to live under their emerald embrace. . . Either in their life, or in their death. What am I?

I am small, but, when entire, of force to set a town on fire! Let but one letter disappear, I then can hold a herd of deer; Take one more off, and then you'll find, I once contained all human kind.

We are very little creatures; all of us have different features. One of us in glass is set; one of us you’ll find in jet. Another you may see in tin, and a fourth is boxed within. If the fifth you should pursue, it can never fly from you. What are we?

Dave and Brad, two popular politicians, met at a club to discuss the overthrow of their party leader. They each ordered a vodka on the rocks. Brad downed his and ordered another. He then drank his second in a gulp and decided to wait before he ordered a third. Meanwhile, Dave, who was sipping his drink, suddenly fell forward dead. Both men were set up for assassination. Why did Dave die and Brad live?

Dr. Miller was staying with his cousin, Alfred, in Alfred’s lakeside cabin. They were setting up Alfred’s will. Since Dr. Miller was Alfred’s closest living relative, much of Alfred’s estate was being left to him. One day, Alfred went to Dr. Miller very upset. “Doctor,” he began, “I have just found out that an old enemy is out to get me. He is coming very soon. Where will I go? Where can I hide? If he finds me, he will surely kill me. I do not have time to leave this cabin and hide in the woods.” Dr. Miller thought for a moment, and then grabbed a 5′ long bamboo fishing pole, with a diameter the size of a quarter. “Alfred, follow me out to the lake. This lake is 4′ deep. If you lie on the bottom of the lake and breathe through this pole, your enemy will never find you. I will be in the bulrushes with a shotgun, and I will shoot him when he comes. I will swim down to find you when he is gone.” Alfred thought that was a great idea and went down to the lake with the bamboo pole in his mouth. A few hours later, a ranger passed by. He found Alfred’s body. Dr. Miller told the police of the circumstance, and that Alfred had probably panicked, and died. Police arrested Dr. Miller on the charge of murdering Alfred. Why?