The distance from the earth to the sun is how many light years
a) exactly one light year
b) any number of light years
c) less than one light year
d) more than one light year

Which statement about the stamps is correct?

If i add water to oil what will happen

15. which of the following is not human-caused groundwater pollution? a. water in an aquifer dissolves elements such as arsenic and mercury from surrounding rock. b. water in an aquifer is contaminated by leachate that seeps into the ground from a landfill. c. water in an aquifer becomes polluted with chemicals used in hydraulic fracturing, or fracking. d. water in an aquifer absorbs harmful bacteria from the drainage field of a septic tank.