Is f(x)=-4x squared -2x-8, concave up or down

Explain why the function is discontinuous at the given number a. (select all that apply.) f(x) = 1 x + 1 a = −1 f(−1) is undefined. lim x→−1+ f(x) and lim x→−1− f(x) exist, but are not equal. lim x→−1 f(x) does not exist. f(−1) and lim x→−1 f(x) exist, but are not equal. none of the above

Quadrilateral abcd in the figure below represents a scaled-down model of a walkway around a historic site. quadrilateral efgh represents the actual walkway. abcd is similar to efgh. what is the total length, in feet of the actual walkway?

Kyle and elijah are planning a road trip to california. their car travels 3/4 of a mile per min. if they did not stop driving, how many miles could kyle and elijah drove in a whole day? ? 1 day = 24 hours. plzzz write a proportion i will give you 100 points