Which of the following plants have swimming sperm a. ginkos b cykads c. both a and b d. none of the above

According to the diagram, what sources contribute to the phosphorus found in soil? according to the diagram, phosphorus found in soil contributes phosphorus to what other sources? (site 1)

The picture shows a fishing technique called trawling. how might trawling affect marine biodiversity

On a spring day, a middle-latitude city (about 40? north latitude) has a surface (sea-level) temperature of 10 ? c. if vertical soundings reveal a nearly constant environmental lapse rate of 6.5 ? c per kilometer and a temperature at the tropopause of –55 ? c, what is the height of the tropopause?