Hannah does an experiment. she has two colorless chemicals that she mixes together in a beaker. which of the following indicates that a chemical change occurs when she mixes the two chemicals together? i. the chemicals change color from colorless to purple. ii. a yellow gas forms. iii. a brown solid forms in the bottom of the beaker. iv. the temperature of the chemicals rises 15°c. a. ii and iii only b. i, ii, iii, and iv c. i and iii only d. i, ii, and iii only

B. I, II, III, and IV

Explanation:

A chemical change occurs when the original substances (the reactants) are changed into a new substance or substances (the products). A chemical change can be indicated by a color change, gas formation, solid formation, or a temperature change. I, II, III, and IV all indicate that a chemical change has occurred when Hannah mixes the two chemicals

answer is a

explanation:

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: