Can someone please help me i need it

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

What is the gcf of 20c^3-5c^4+30c^6

20 ! jason orders a data set from least to greatest. complete the sentence by selecting the correct word from each drop-down menu. the middle value of the data set is a measure and is called the part a: center b: spread part b: mean a: mean absolute deviation b: median c: range