Answer:
Pteridophytes are vascular plants but they do not produce flowers and seeds which mean their source of reproduction is unknown or hidden.
On the contrary, Spermatophytes as the name indicates, are seed bearing plants. They produced seeds and flowers. Examples are flowering plants, cactus, leather flower, buttercup and may more.
Explanation:
The correct answer is B, internal intercostal muscles and abdominal muscles would contract.
Exhalation is the flow of the breath out of the body. During forced exhalation, internal intercostal muscles contracts which lower the rib cage and decrease thoracic volume, while the abdominal muscles push up on the diaphragm which causes the thoracic cavity to contract.
That's called a convex lens, as they converge.
It is not a mineral because it is man made!