1 Explain that a population pyramid shows the age and sex structure of a population. 2  Point to the horizontal bars, which show the percentage (or the absolute number) of males and females in each age group. 3  Have students interpret the chart.
1 Although they range from $150-$400 or more, a large capacity (25-70 pints) dehumidifier for a basement (the dampest portion of most homes) or other large area averages $200-$300.
Posted July 11 2010 - 6:43 AM. I always hear the radio ads for the Wave ventilation system to expel damp air from the basement. I'm interested as I want something better than my dehumidifier. I did a search online and found the cost to be around $1700. I then found a post by a guy who made his own which I'm thinking of trying.