From a balcony of a building located at the dead-end of a street, John is planning to hit people coming toward his building with flowers. For this, John makes a red-colored mark on the road so that the moment he sees a person at that mark he throws a flower at a speed of 5ms−1 at an angle of 60o with vertical. Assuming that people approach the building at 3ms−1 and if the distance of the point where flower hits a person from the red-colored mark is 10m: (a) find the distance of red-colored mark from the base of the building,
(b) find the height of balcony from the ground, and
(c) just before the flower hits a person, find the horizontal and vertical components of its velocity.

Which of the following are risk factors for emphysema ? correct answer : a and and c          good luck and have a nice benevolentpuppy day! : )

I'd go for the one that says that knees are fulcrums, lower legs are levers and the ankles hold loads.hope it ,happy homework/ study/ exam!

The figure is missing but we can answer anyway.the correct answer is "releasing the string". in fact, when the person is holding the bow and the arrow, the kinetic energy of the arrow is still zero (because the arrow is not moving). the moment the arrow is released, it acquires a velocity v, so its kinetic energy will become different from zero: where m is the mass of the arrow and v its velocity.  all the other options, instead, do not increase the kinetic energy of the system: -  pulling farther back on the string : this will just increase the elastic potential energy of the system-  holding the arrow higher: this will increase the gravitational potential energy of the system (which is given by u=mgh, where h is the height above the ground)-  decreasing the mass of the arrow: this will decrease the gravitational potential energy of the system (which is given by u=mgh, where m is the mass)