PLEASE HELP ME WILL MARK BRAINLIEST!
An icicle drips at a rate that can be represented by the function f(x) = −x2 + 8x − 7, where 0 ≤ x ≤ 10 and x is the number of hours after the sun has risen. When f(x) is a negative number, the icicle is not dripping. Determine the values when the icicle starts and stops dripping.

A. x = −1 and x = 7
B. x = 1 and x = 7
C. x = 1 and x = −7
D. x = −1 and x = −7

Tom had a total of $220 and he spent $35 on a basketball ticket . what percent of his money did he have left?

Kayla wants to find the width, ab, of a river. she walks along the edge of the river 65 ft and marks point c. then she walks 25 ft further and marks point d. she turns 90° and walks until her location, point a, and point c are collinear. she marks point e at this location, as shown. (a) can kayla conclude that δ and δ are similar? why or why not? (b) suppose de = 15 ft. what can kayla conclude about the width of the river?

What is the radical expression that is equivalent to the expression 27 1 over 5?