In this task you will be given a passage and a yes/no question based on the passage. You should answer the question using the information from the passage.

passage: In popular usage, the word ``undertow'' is often misapplied to rip currents. An undertow occurs everywhere underneath shore-approaching waves, whereas rip currents are localized narrow offshore currents occurring at certain locations along the coast. Unlike undertow, rip currents are strong at the surface.
 question: is an undertow the same as a rip current?
No

passage: Estrogens are synthesized in all vertebrates as well as some insects. Their presence in both vertebrates and insects suggests that estrogenic sex hormones have an ancient evolutionary history. The three major naturally occurring forms of estrogen in females are estrone (E1), estradiol (E2), and estriol (E3). Another type of estrogen called estetrol (E4) is produced only during pregnancy. Quantitatively, estrogens circulate at lower levels than androgens in both men and women. While estrogen levels are significantly lower in males compared to females, estrogens nevertheless also have important physiological roles in males.
 question: is there such a thing as natural estrogen?
Yes

passage: Although a pendulum can theoretically be any shape, any rigid object swinging on a pivot, clock pendulums are usually made of a weight or bob attached to the bottom end of a rod, with the top attached to a pivot so it can swing. The advantage of this construction is that it positions the centre of mass close to the physical end of the pendulum, farthest from the pivot. This maximizes the moment of inertia, and minimises the length of pendulum required for a given period. Shorter pendulums allow the clock case to be made smaller, and also minimize the pendulum's air resistance. Since most of the energy loss in clocks is due to air friction of the pendulum, this allows clocks to run longer on a given power source.
 question: does the weight of a bob effect a pendulum?

Yes