After carefully watching the video, choose THE BEST Claim in regards to why human skin color varies throughout the world. A. Primates have light skin color under their dark hair so when humans began to evolve and lose body hair, that pigment needed to go into their skin so they could still blend in with their surroundings.
B. Darker melanin is beneficial for reproduction in areas where ultraviolet (UV) light is high, and can negatively affect reproduction in areas of low UV light.
C. Darker melanin is beneficial under intense UV light because it protects from skin cancer, absorbing the UV light. Under low UV light, producing excess melanin uses too much energy, therefore it is more beneficial (energy saving) to produce less melanin in low UV light areas.
D. Humans evolved as separate populations, around the equator and towards the poles, so skin pigment color (melanin) was naturally different in those areas.

Tara sees a commercial for a brand of pills that promise to boost energy and people perform better in work and school. as people in the commercial talk about how much better they feel when taking the pill, tara notices a message on the bottom of the screen that reads, "this pill is not approved by doctors and has not been tested in controlled experiments." what is the best conclusion that tara should make about the commercial? it is making scientific claims based on subjective observations. it is making scientific claims based on opinions instead of pseudoscientific facts. it is making pseudoscientific claims based on objective observations. it is making pseudoscientific claims based on opinions instead of scientific facts.

Select the situation bellow that would produce a total displacement of zero. a. a trip to the moon and then to mars b. a horse galloping from one end of a field to another c. the criss-crossing path of a bug as it flies from flower to flower d.a round-trip ride to school and back

Consider the motion of the balloon and its air contents in terms of momentum. in step 1 above, the total momentum of the balloon and its contents was zero. recall that momentum = mv. both the balloon and the air inside it had a velocity of zero and therefore the total momentum was zero. now think about what happened when the air escaped from the balloon. a certain mass of air accelerated in one direction. in order to keep the total momentum of the system zero, the balloon itself (which has mass) had to accelerate in the opposite direction. use this scenario to you explain why the soda can rotates when the water squirts out of the escape holes. what was your hypothesis concerning the water-filled can? according to your data, do you think your hypothesis was correct? (be sure to refer to your data when answering this question.) summarize any difficulties or problems you had in performing the experiment that might have affected the results. describe how you might change the procedure to avoid these problems. give at least one more example of newton's third law in everyday life.