The resulting imbalance between incoming solar radiation and outgoing thermal radiation will likely cause Earth to heat up over the next century, accelerating the melting polar ice caps, causing sea levels to rise and increasing the probability of more violent global weather patterns.
Ocean fossils found on the rocky mountains are because of tectonic plates crashing.
They provided silk
Hope this helped
The Wisconsin River originates in the forests of the North Woods Lake District of northern Wisconsin, in Lac Vieux Desert near the border of the Upper Peninsula of Michigan. It flows south across the glacial plain of central Wisconsin, passing through Wausau, Stevens Point, and Wisconsin Rapids. In southern Wisconsin it encounters the terminal moraine formed during the last ice age, where it forms the Dells of the Wisconsin River. North of Madison at Portage, the river turns to the west, flowing through Wisconsin's hilly Western Upland and joining the Mississippi approximately 3 miles (4.8 km) south of Prairie du Chien.
Set this up as
10 = 40 (1/2)t/28
and solve for t in years.
10/40 = (1/2)t/28
log(0.25) = (t/28) log(0.5)
t = 28 log(0.25) / log(0.5) years = 56 years
Test the answer:
56 years = 2(28 years) = 2 half-lives, so the remaining amount should be 1/2 of 1/2 of the initial amount, i.e. 1/4 of the initial amount, and 10 mg = 1/4 of 40 mg.