# Don’t Be Shy!

Just a quick reminder:

You are always welcome to visit office hours or make appointments with me, Kaley or John regarding the quizzes (or anything else about the course).

Unfortunately, Penn State Learning is not equipped to help students with Math 33 at this time since the course is still new. So we encourage you to get help directly from us.

Don’t be shy! Come say hi!

# Scales and Scientific Notation

On Friday’s class, we talked about how large astronomical bodies can get, but we did not look at the numbers. We also did not talk about the small objects scientists study like DNA, molecules, atoms, high-energy waves like gamma rays and subatomic particles like electrons.

To find the numbers for particular scales you can check out this list here: http://www.falstad.com/scale/

These numbers can provide a point of reference when you are trying to estimate values.

A fun interactive that helps you develop a sense of these scales can be found here: Scale of the Universe 2. To navigate the scales, use the sliding bar at the bottom. I’ve posted a screenshot of the software below, which shows how a white blood cell, a red blood cell, e-coli, a clay particle, an x-chromosome, a y-chromosome, red light and violet light compare.

# Why Should You Recycle?

The image to the left comes from a flyer I saw in the Life Sciences building this past december. The flyer provides a number of figures that are meant to persuade you to recycle.

Do they make sense based on your experience? Do they provide the information you need to decide whether or not to recycle? Take a moment to analyze the statements regarding paper, water, tin (perhaps they mean aluminum instead), glass, and plastic. Are each of these figures are sufficient for explaining why recycling is effective? Be sure to explain your reasoning.

# Greenhouse Gases, Overpopulation, and Agriculture

One of the most energy and resource intensive human activities is harvesting food, mostly because we have so many people to feed. And the population is only growing. There have been a variety of responses to this dilemma, three of the big ones being

1. to genetically engineer crops and livestock to produce more food with less resources,
2. optimize farming practices to reduce waste (e.g. organic farming), and
3. reduce the consumption of foods that are energy intensive (e.g. beef) or whose harvesting lead to unacceptable levels of environmental degradation (e.g. palm oil).

Unfortunately, each of these approaches faces major obstacles. The public is reticent to embrace genetically engineered foods, primarily because of perceived risks. Organic farming is not only expensive, but requires more space for the same crop yields as conventional farming. Reducing the consumption of energy intensive foods like meat and dairy–something advocated by the United Nations and the Environmental Working Group— is wildly unpopular. In the case of detrimental crops like palm oil and bananas, most people aren’t even aware there is an environmental problem.