1 The level of significant difference you are hoping to show (e.g. p p value takes more study power. 2  The frequency of the outcome in the two groups. 3  Imagine an exposure that increases incidence by a third: it is easier to show a difference between 30 and 45 percent than between 10 and 15 per cent.
Name of Instrument: Bass drum. Family: Percussion. How to Play: The bass drum is played by using padded beaters or sticks and striking it against the drumhead. In a drum set, the musician plays the bass drum by using a pedal-operated stick. Types: The bass drums that are used in marching bands and military music have two drumheads.
Percussion instruments are classified as tuned or untuned. Tuned instruments play specific pitches or notes, just like the woodwind, brass and string instruments. Untuned instruments produce a sound with an indefinite pitch, like the sound of a hand knocking on a door.nare drum. The snare drum has a crisp untuned sound that is used by the military and in marching bands. Sometimes called the side drum, the snare drum has two heads made of skin stretched over a hollow metal frame. The top head is struck with wooden drumsticks, and is called the batter-head.