Which phrase describes one characteristic of radioactive elements? are produced in a laboratory
decay at a constant rate
have a consistent number of particles
release energy and particles to maintain radioactivity

Which type of organism is missing from the food web seen in the illustration? primary consumers decomposers primary producers secondary consumers

Hydrilla (hydrilla verticillata) is an invasive aquatic plant and one of the most serious aquatic pests in florida. hydrilla has already been introduced to hundreds of bodies of water throughout florida, hydrilla is difficult to control because it grows rapidly and survives in many different water depths and conditions. hydrilla • describe how hydrilla affects native plant and animal species. include both a biotic and an abiotic limiting factor. • suggest one biotic and one abiotic recommendation that could slow the spread of hydrilla

What environmental cues and landmarks do the geese use to determine the timing and direction of their migration over the mountains? how do they find their way?