X2 (average) = (2.36+2.38+2.48+2.50+2.42)/5 = 2.428 Error =2.50-2.428=0.072.
2. The average number of additional periods = (427+439+428+438+436+440+432+435+436+439)/10 = 435.
Distance = 435 *100/22 =1977.3 (m)
3.36000*0.25+ 30000*0.3+20000*0.4+ 15000*0.5=9000+9000+8000+7500=33500
36000+30000+20000+ 15000= 10 1000
n = 33500/ 10 1000 = 0.33