30points

1) the function f(x) varies directly with x and f(x)= 160 when x=40. what is f(x) when x=8?
a)32
b)20
c)5
d)2
2)the function f(x) varies inversely with x and f(x)=2 when x=16. what is f(x) when x=4?
a 128
b 72
c 40
d 8
3)the pressure of a gas p(v) varies inversely with the volume of the gas v. the pressure of a gas measures 15kg/cm² when its volume is 300cm³. which equation can be used to find the pressure of the gas when the volume is changed?
a p(v)=20v
b p(v)=20/v
c p(v)=4500v
d p(v)=4500/v
4)the scale factor of the blueprimt of a shopping mall to the actual shopping mall is 1in/18ft. the area of the mall on the blueprint is 190in². what is the area of the actual shopping mall?
a 61,560ft²
b 36,118ft²
c 6840ft²
d 3420ft²
5)the scale factor of a model of a grain silo to the actual silo is 1 to 10. the volume of the actual silo is 550m³. what is the volume of the model?
a 0.55m³
b 2.75m³
c 5.5m³
d 27.5m³