Ledder G Mathematical Modeling for Epidemiology and Ecology 2ed 2023

• ULTIMATE ROCK COLLECTION FOR KIDS - A perfect standalone collection or addition to any kid's rock collection. Includes rough and polished samples of aventurine, rose quartz, stunning snowflake obsidian, desert rose, red jasper, blue quartz, pumice, and geode specimens as well. Makes an excellent STEM gift for girls and boys!
  
• GENUINE FOSSILS - real fossils include prehistoric gastropods, ammonites, clams, brachiopods, and more. The included magnifying glass, full-color learning guide, and identification sheet will help you to sort and identify every rock, gemstone, mineral, and fossil in the collection.
  
• REAL GEODES – Discover crystals treasures! Each kit contains one broken geode and two unbroken geode specimens for you to crack open yourself. Geology doesn't get more exciting than breaking open rocks and finding crystal treasures.
  
• DISPLAY YOUR FAVORITES – Show off your favorite rock, crystal, and fossil specimens in the included case! Keep the rest of your treasures safe in the included storage bag.
  
• HIGH-QUALITY EDUCATIONAL TOYS - We're proud to make the highest quality hands-on science toys, and all our products are backed by exceptional service. If your experience is less than stellar, let us know and we'll make things right!