A taxi company is trying to decide whether to purchase brand A or brand B tires for its fleet of taxis. To estimate the difference in the two brands, an experiment was conducted using 12 of each brand. The results are as follows

BrandA:x ₁=36300 km , S₁ = 5000km

BrandB:x ₂ = 38100 km ,S₂= 6100km

1. (a)testifthetwopopulationvariancescanbetreatedtobeequal.Use=0.05
2. (b)basedontheconclusioninpart(a),constructa95%confidenceintervalforABassumingthepopulationstobenormallydistributed
3. (c) Can you conclude if the two population means are equal at 5% level of significance