A 5 kg block moves with a constant speed of 10 to the right on a smooth surface where frictional forces are considered to be negligible. It passes through a 2.0 m rough section of the surface where friction is not negligible, and the coefficient of kinetic friction between the block and the rough section He is 0.2. What
is the change in the kinetic energy of the block as it passes through the rough section?
A
20 J of energy is removed from the block.
B
250 J of energy is removed from the block.
с
20 J of energy is added to the block.
D
250 J of energy is added to the block.

You have been consulted by the mobile phone company hookup about a new augmented reality product called “brows”. they want to develop an alternative to google glasses, which, you recall, is a proposed new product which plans to superimpose a whole range of wireless google services over the user’s ordinary vision of the world. these appear in little circles and ovals, and let you phone people, take photographs, navigate across cities and inside buildings, find shops and update your social media. brows would do this too, but not be limited to special google services. the user would wear a small cylinder-shaped device designed to fit on top of their existing eyewear (glasses or sunglasses). it would project a reversed image onto the inside of the lenses, the reflection of which would be in focus for the user. instead of voice control, the user would control the device by eye and neck movements, which the device would track. the device would connect via bluetooth to the user’s phone, which would supply most of the computing power and wireless connectivity. hookup also wants to know what existing services would be most in demand, and which would not work well with brows. using your knowledge of augmented reality, wearable technology and interface design, is the project feasible? if not, why not? if feasible, how could the product need to be modified for a better experience?

Apatient has a history of poor nutrition. he has skin rashes, bleeding gums, and a cut that hasn’t healed in a long time. what vitamin deficiency most likely caused this symptom?

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?