A small hole in the wing of a space shuttle requires a 16.4 cm² patch. (a) What is the patch's area in square kilometers (km²)? Enter your answer in scientific notation.
X 10
km2
(b) If the patching material costs NASA $2.89/in?, what is the cost of the patch to the nearest cent?

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.