Question 1
A study was designed to investigate the effects of two variables — (1) a student's level of mathematical anxiety and (2) teaching method — on a student's achievement in a mathematics course. Students who had a low level of mathematical anxiety were taught using the traditional expository method. These students obtained a mean score of 470 with a standard deviation of 50 on a standardized test. Assuming a non-mound-shaped distribution, what percentage of the students scored over 620?
◦ at most 11%
◦ at least 89%
◦ at most 5.5%
◦ approximately 2.5%
Question 2
A recent survey was conducted to compare the cost of solar energy to the cost of gas or electric energy. Results of the survey revealed that the distribution of the amount of the monthly utility bill of a 3-bedroom house using gas or electric energy had a mean of $104 and a standard deviation of $10. If nothing is known about the shape of the distribution, what percentage of homes will have a monthly utility bill of less than $84?
◦ at least 88.9%
◦ at most 25%
◦ at most 11.1%
◦ at least 75%
The first published illustration of a camera obscura observing a solar eclipse.
A roller cell-type electric fuel pump.
What Happens to Incoming Solar Radiation?
Concentrated solar towers
Energy in a Circular Orbit
how much energy is needed to heat 77.0g H2O(s) from -10.0 C to 0.0 C?