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 produce sound when they are struck or shaken. Their name, percussion, means the hitting of one body against another.. In the orchestra, the percussion section provides rhythm and tone color.Percussion instruments are made from many materials, but usually consist of either a solid material or a stretched membrane (thin material).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.