BEST GETS BRAINLIEST JUST NEED CONFIRMATION TAHT I GOT IT RIGHT ANY HELP IS APPRECIATED

Sanya noticed that the temperature was falling at a steady rate of 1.4 degrees every hour from the time that she first checked her outdoor thermometer. by 6 a.m., the temperature had fallen 21 degrees. which expression can you use to find how many hours earlier she had first checked the thermometer?

Rectangle bcde is similar to rectangle vwxy. what is the length of side vy? a) 1 7 b) 2 7 c) 3 7 d) 4 7

What is 100,000 times 1/100,000, using the standard method of multiplication? write the answer as 10 to a power.