2. the table shows the soil density of several soil samples at different depths. depth (m) 1 5 6 8 10 12 14 21 23 24 28 soil density ( ) 1045 1063 1102 1140 1191 1232 1249 1254 1265 1268 1273 (a) write the quadratic regression equation that models the data. let x = depth below the surface and let y = soil density. (b) use the equation to estimate the soil density of a sample at a depth of 20 m. show your work.

Ray ce is the angle bisector of zacd, which statement about the figure must be true? mzecd-mzecb mzace « 4mzacd zace - zdcb zecd zacd save and exit

Adecibel is a logarithmic unit that can be used to measure the intensity of a sound. the function y = 10logx gives the intensity of a sound in decibels, where x is the ratio of the intensity of the sound to a reference intensity. the reference intensity is generally set at the threshold of hearing. use the graphing utility to graph the decibel function. a whisper has a sound intensity of 30 decibels. use your graph to you complete the following statement. the sound intensity of a whisper is times the reference intensity.

Aschool allots ? 1500 to spend on a trip to the theatre. theatre tickets have a regular cost of ? 55 each and are on offer for 1 5 off. a train ticket for the day will cost ? 12 each. if 2 teachers and the maximum number of students attend, how much money will the school have left over?