Assertion: Addition of HCI to Copper(II)Oxide changes the colour of solutionfrom blue-green toblack. Reason: HCI neutralizes Copper(1) Oxide and Copper(11)Chloride is formed.​

b i think it’s a water wheel turning in a stream

in cartography, a contour line (often just called a "contour") joins points of equal elevation (height) above a given level, such as mean sea level. a contour map is a map illustrated with contour lines, for example a topographic map, which thus shows valleys and hills, and the steepness or gentleness of slopes.

explanation:

aquifers are bounded above and below by impermeable rock. the driving force of groundwater movement in confined aquifers is pressure, rather than gravity.