
velocity is a vector so it has a magnitude and direction so the answer would be B
"A. labelling food supplies" and "B. monitoring water supplies" are both public health measures that have helped fight disease. Vaccinations are essential to public health.
I think that correct answers are:
<span>Some of them lose their leaves in winter. (i.e. <span><em>Larix</em></span>)</span>
<span>They include the tallest plants (i.e<em>.Sequoia)
</em>I don't think they are the oldest type of seed plants, since in the past the classes like progymnosperms and seed ferns existed prior to the gymnosperms. But question isn't absolutely clear to me and I can't be 100% sure.
All of the gymnosperms have seeds unless human grows some seedless variant.
Gymnosperms don't have flowers like angiosperms do, but some people think that cone is kind of flower.
Male cones produce pollen, not female.
Hope I helped :)
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