Proving triangles congruent

Prove that the sum of two consecutive exponents of the number 5 is divisible by 30.if two consecutive exponents are 5n and 5n + 1, then their sum can be written as 30.

Which is the graph of f(x) = (4)x? image for option 1 image for option 2 image for option 3 image for option 4

If a 36 inch yardstick casts a 21 foot shadow, how tall is a building whose shadow is 168 feet? what is the scale factor