During the school year, gianna usually keeps a regular sleeping schedule. she goes to bed at 9: 15 p. m. and wakes up at 6: 30 a. m. for how long does gianna sleep on a school night? express the answer in hours and minutes.

The decibel level of sound is 50 db greater on a busy street than in a quiet room where the intensity of sound is watt/m2. the level of sound in the quiet room is db, and the intensity of sound in the busy street is watt/m2. use the formula , where is the sound level in decibels, i is the intensity of sound, and is the smallest sound intensity that can be heard by the human ear (roughly equal to watts/m2).

Which undefined geometric term is described as a location on a coordinate plane that is designed by an ordered pair (x,y) ?

Find the exact value of sin 3.14/12