If (54)" = 512. What is the value of m?

What is the sum of the first 8 terms of the geometric series

Me i’m stuck on all these questions besides the two bottom ones

Th perimeter of a rectangular garden is 150 feet. the length is 50 feet longer than the width, w. which equation could be used to calculate the width of the garden? a.) 2w+ 2(w-50) =150 b.) 2w+50 + 2w =150 c.) 2(w+50) + w =150 d.) 2w+ 2(w + 50) = 150 need asap. will give brainliest !