For radioactive decay:
N = N(0) x exp(-λt), where λ is the decay constant equivalent to ln(2)/half life, N is the amount after a given amount of time, t is the time passed and N(0) is the initial amount.
1)
N = 24 x exp(-ln(2)/4.5 x 36)
N = 0.09375 mg
2)
1.2 = 9.6 x exp(-ln(2)/4.5 x t)
ln(1.2/9.6) = -t x ln(2)/4.5
t = 13.5 days
A flashback, is a way of portraying events in the past to understand the current event that is connected to the present, that a could support in figuring the conclusion and answer to the problem of an event. I think the author use it as said in the definition. I hope this would help
Answer:
Option C.
Psilotum.
Explanation:
Psilotum is a genus of whisk ferns. They are vascular plants. They lack true stem and true leaves, their stems is the organ that contain the conducting tissues. They have stems with many branches and synangium with three lobes. The synangia is is fused sporangia that produce spores. They have rhizome which form rhizoids and help to anchor the psilophyte sporophyte.
Digestive system:
<span><span>· </span>The mouth-the start of digestion, where the food is chewing and breaking</span> <span><span>· </span>The pharynx- receives the food from the mouth</span>
<span><span>· </span>The esophagus- a muscular structure which carries food to the stomach via contractions</span>
<span><span>· </span>The stomach- sac-like organ which serves as the mixer and grinder of food, secretes acids and enzymes</span>
<span><span>· </span>Small intestine (the duodenum, jejunum, and ileum)-here, the food is broken down using enzymes released by the <span>pancreas and bile from the </span>liver</span> <span><span>· </span>Large intestine (the colon, rectum, and anus)-<span> for processing and excretion of waste.</span></span>
