Do the angles of a triangle always add up to 180?

Ineed with number 6 , explain how to get 1978

Carly stated, “all pairs of rectangles are dilations.” which pair of rectangles would prove that carly’s statement is incorrect?

Suppose a laboratory has a 30 g sample of polonium-210. the half-life of polonium-210 is about 138 days how many half-lives of polonium-210 occur in 1104 days? how much polonium is in the sample 1104 days later? 9; 0.06 g 8; 0.12 g 8; 2,070 g