Please help this is timed

What is the missing reason in the proof? segment addition congruent segments theorem transitive property of equality subtraction property of equality?

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

Dylan is evaluation the expression 13+19+7+10 at one step in his work, dylan rewrites the equation as 13+7+19+10 which property of addition must dylan have used when he evaluated the expression?