Keratin, a type of protein that is a basic component of hair, skin and nails and helps create an intact barrier.
Crab grass does so well when ordinary grass struggles in late summer
because its seed germination is higher when exposed to hotter
temperatures.
The seeds of crab grass are mostly dormant and their germination is
dependent on the soil temperature. During summer, the temperature of the
soil is usually higher which aids its growth .
This therefore explains the reason why crab grass does well than ordinary
grass in late summer periods.
Read more about Crab grass brainly.com/question/7601938
i have the answer and it says C
<span>They are made up of nitrogen bases, sugars, and phosphates.
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