Abby is registering at a Web site and must select a six-character password. The password can contain either letters of digits. a. How many passwords are possible if characters can be repeated? If no characters can be repeated?
b. How many passwords are possible if all characters are letters that can be repeated? If the password must contain exactly one digit? Which type of password is more secure? Explain.

the answer is d. 75%

5

step-by-step explanation:

fd

step-by-step explanation:

answer: the sun

explanation:

water cycle describes the evaporation of water from earth's surface, formation of clouds and precipitation water back onto the surface of earth. seventy percent of the earth is covered with water in the form of seas and oceans. the heat of the sun causes the evaporation of water from the surface of the ocean. the water vapors rise and condense to form water droplets. the collection of these water droplets form clouds which rain down again.

the evaporation of the oceans surface water as part of the water cycle is caused by the sun