The local dealerships sold a total of 81 vehicles. How many more vehicles were sold by Truck City than by RV City? I NEED HELP ASAP

Can someone, me with this.i really need with this

What is the approximate difference in tenths between √12 and √15?

Astudy found that the variance in the number of vehicles owned or leased by subscribers to a magazine is .094. assume a sample of 12 subscribers to another magazine provided the following data on the number of vehicles owned or leased: 1,1,1,0,3,2,1,1,2,1,0, and 1 a) compute the sample variance in the number of vehicles owned or leased by the subscribers (to 4 decimals). b)test the hypothesis to determine whether the variance in the number of vehicles owned or leased by subscribers of the other magazine differs from .calculate the value of the test statistic (to 3 decimals).