A=6 because 54/9=6
For b, the picture is not very clear and so I can’t see properly but if it says b/3 then b=45 because 15•3=45
c=11 because 23-12=11
It would cost somehow less than $1000 and you would know that because 347 students is a large number, but since it hold 44 students in each bus, it’ll take not to long to get to 347. So since each bus is $95, it would at least reach to 700+
(All is estimated)