Cathy is pedaling down a steep hill on her bicycle and wants to be able to coast up the next hill, which is 25 meters high, without pedaling. cathy and her bicycle have a mass of 75 kg. assuming her bicycle is 100% efficient, what would her speed have to be?

Point charges q1=+2.00μc and q2=−2.00μc are placed at adjacent corners of a square for which the length of each side is 1.50 cm . point a is at the center of the square, and point b is at the empty corner closest to q2. take the electric potential to be zero at a distance far from both charges. part a what is the electric potential at point a due to q1 and q2? express your answer with the appropriate units.

Is a volume of space that is empty of matter.

Which of the following is true about fossils? a. fossils found in lower layers of sedimentary rock are older than fossils found in upper layers of sedimentary rock. b. fossils found in lower layers of sedimentary rock are as old as fossils found in upper layers of sedimentary rock. c. the relative age of fossils cannot be determined from their position in sedimentary layers.