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.
It is likely that there was no single inventor of the modern orchestral bass drum but that it evolved multiple times across Europe as the sound began to be incorporated into musical compositions. The smaller, rock or pop bass drum came into existence with the invention of the bass drum pedal in 1909: