Because it’s time consuming and money consuming to observe from space so models are required
Testosterone is the principal male sex hormone.
The answer is (1.) entering the torpor
The hummingbirds are the tiniest bird in the world but is
also the biggest eater. They burn food so fast they often eat up to 3 times
their weight. They feed on nectars and insect. When they can’t eat especially
on cold temperatures, these birds go in a sleeping state called torpor. A
fascinating way to conserve energy.
I believe the answer is <span>D. Examining the different layers of heart tissue</span>
