Help me with this please

Determine if the sequence is geometric. if it is, find the common ratio. 1) -2, 2/3, -2/9, 2/27 2) 0,2,5,9 3) 2, -10, 50, -250 4) 1,4,16,64

Prove that the value of the expression 7^8–7^7+7^6 is divisible by 43.

Lines b and c are parallel. what is the measure of 2? m2 = 31° m2 = 50° m2 = 120° m2 = 130°