Ajar contains only one blue tile, one green tile, one red tile, and one yellow tile. if a tile is chosen at random and then replaced in the jar, and then a second tile is chosen at random, how many of the possible outcomes contain at least one red tile?

Multiplying an even number of negative numbers gives an answer that is choose from:

Arley is building a model of a city map. in one part of the city, three roads form a right triangle, which harley draws as triangle abc, with the following measures: m∠b=90° and m∠a=30°. in his scale model, the hypotenuse of triangle abc, ac¯¯¯¯¯¯¯¯, has a length of 817−−√ cm. what is the value of a (the length of bc¯¯¯¯¯¯¯¯)?

The radius of the earth is two times the radius of the moon. what fraction of the volume of the earth is the volume of the moon?